Is photography better by substitution or addition?
Subtraction and addition in photography had their own unique uses, and there was no absolute advantage in either. The main purpose of the use of Subtraction in photography was to highlight the subject and simplify the picture. For example, one could use a large aperture at the telephoto end to make the depth of field shallow and the background blurred to reduce the interference elements in the picture; choose a suitable shooting angle such as an overhead shot or an overhead shot to change the relationship between the subject and the background to highlight the subject; remove elements unrelated to the subject through post-processing software, etc. When there were many elements in the scene, it could make the scene simple and clear, allowing the viewer to quickly focus on the subject. In photography, addition could add liveliness and emotional depth to the picture. For example, adding background elements when shooting scenery or flowers to make the picture more beautiful, and arranging people's activities when shooting static pictures such as snow scenes to make the picture more dynamic, romantic and poetic. When there were few elements in the picture and it was slightly monotonous, addition could enrich the content of the picture. In actual photography creation, one needed to flexibly use the addition and deduction according to the specific shooting scene, the shooting theme, and the emotions they wanted to express. Read more exciting novels for free
Simple decimals, addition, and substitution
1. ** Calculation Method **: - The decimals had to be aligned, which meant that the same digits had to be aligned. For example, if you calculate 3.25+1.7, the first digit after the decimal point of 3.25 is 2, and the first digit after the decimal point of 1.7 is 7. After this, you can calculate. - Starting from the lowest position, each of you must enter one out of ten. For example, if you want to calculate <1.9 + 0.8>, you first calculate <9+8 = 17>, then move one forward from ten. The first digit after the decimal point is <7>, and then calculate the integral part of <1 + 0+1 = 2>. The final result is <2.7>. - If it wasn't enough to reduce, he had to borrow from the previous digit and reduce it again. For example, if the calculation of 3.1 - 1.8, 1 - 8 is not enough, then borrow 1 from 3 to become 10, 10+1 - 8 = 3, the integral part 3 - 1 - 1 = 1, the result is 1.3. - When the minuend was an integral number, a decimal point had to be added, and then a "0" had to be added according to the decimal part of the minuend. For example,"5 - 3.25", write "5" as "5.00", and then subtract. - When calculating the addition and deduction of decimals in the vertical form, the "0" at the end of the decimal point could not be removed. When the result was written in the horizontal form, the "0" at the end of the decimal point had to be removed. For example, if you calculate the value of [3.20+1.80 = 5.00], the two [0] in the vertical form of [5.00] cannot be removed, but the result written in the horizontal form is [5]. 2. ** Simple calculation **: - Commutative law of addition: <a + b=b + a>, for example,<1.2+3.8 = 3.8+1.2 = 5>. - The law of additivity: <a + b + c=a+(b + c)>, for example,<1.2+3.8+0.5=(1.2 + 3.8)+0.5 = 5+0.5 = 5.5>. - Commutativity and association of addition: ((a + b)+c = a+(b + c)=(a + c)+b). - Subtraction properties: <a-(b + c)=a - b - c>, for example,<5-(1.2+1.8)=5 - 1.2 - 1.8 = 2>. - Other simple methods: <a-(b - c)=a - b + c=(a + c)-b>,<a - b + c - d=a + c-(b + d)>. 3. ** Same level calculation rules **: - If an equation had both addition and deduction, or if an equation only had multiplication and division, these were all operations of the same level. The normal order of calculations for the same level was from front to back. - You can also move with symbols, such as <3.6+1.4 - 1.6 = 3.6 - 1.6+1.4 = 2+1.4 = 3.4>. When adding the parenthesis, it could be operated according to the formula "add unchanged minus change", such as "5.17-(1.8 - 3.2)=5.17 - 1.8+3.2". <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Reflection on the teaching of addition and substitution, short summary is insufficient
There were some shortcomings in the teaching of addition and substitution: 1. ** Review Lead-in Stage **: The number of mental arithmetic questions may be small, and some students may not be able to participate fully, resulting in distraction. For some key knowledge, such as finding the least common multiple, if they did not review it enough before class, it might affect the speed of subsequent calculations. 2. ** Student Exploration Stage **: Not enough attention is paid to students with learning difficulties. They often put their energy on students who are good at expressing themselves or whose grades are above average, thus ignoring the learning needs of individual students with learning difficulties. 3. [In-class training segment: The effect is not good when students are used.] Although the average students could solve the questions, the form was not standardized. The students with learning difficulties had difficulty solving the questions, while the top students had nothing to do, resulting in a waste of classroom time and unable to meet the learning needs of students at different levels. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
How to write the reflection on the teaching summary of addition and substitution
The reflection on the teaching of addition and substitution could be written from the following aspects: ** I. Achievement of teaching objectives ** 1. ** Knowledge and Skills ** - Whether the student can accurately understand the concepts of the commutative law of addition, the association law, or the addition and substitution of scores. For example, in addition, whether the student understood the position and invariable of the addend (the commutative law of addition), and whether the student had mastered the calculation skills such as general fraction in fraction addition and substitution. They could review the class questions, homework, and test results to see how well the students had mastered the rules of addition and multiplication. - Can the student apply the knowledge of addition and substitution to practical calculation problems, including simple addition and deduction of numbers, decimals, or scores, as well as some comprehensive mathematical problems? 2. ** In terms of process and method ** - Observe the development of the students 'thinking process in the process of learning addition and deduction. For example, when exploring the law of addition, whether the students could obtain the law through observation, comparison, induction, etc.; in the teaching of fraction addition and substitution, whether the students could use transformation ideas (such as transforming different decimal points into the same decimal points) to solve the problem. - To evaluate whether the teaching methods used in the teaching process will help the students master addition and multiplication. For example, whether group cooperative learning promoted the communication between students and their understanding of knowledge, and whether multi-media teaching resources helped students better understand abstract computing concepts. 3. ** Emotions, attitudes, and values ** - To assess the students 'interest and participation in the process of learning addition and multiplication. For example, whether the introduction of interesting mathematical situations stimulated the students 'curiosity about addition and substitution, whether the classroom interaction was positive, and so on. - Pay attention to the students 'attitudes when faced with difficulties in addition and multiplication, whether they actively try to solve the problem or give up easily, and the emotional experience such as the sense of accomplishment after solving the calculation problem. ** 2. Teaching content ** 1. ** Selection and organization of content ** - Check if the difficulty level of the teaching content is suitable for the student's learning level. If the teaching content was too simple, the students would feel that it was not challenging enough, and if it was too complicated, it might cause the students to feel frustrated. For example, in the teaching of addition and substitution of different decimators, whether the teaching content of general fraction was reasonably explained and expanded according to the students 'existing knowledge base. - Is the teaching content organized? For example, the students would be taught from simple to complex (such as adding and deducting whole numbers first, then decimals, and adding and deducting fraction), and whether the transition between the various knowledge points was natural or not, and whether it would help the students build a complete knowledge system of addition and substitution. 2. ** Depth and breadth of content ** - He thought about whether he had dug deep into the key content (such as law calculation, arithmetic, etc.) in the addition and substitution operation teaching. For example, in the teaching of the law of additivity, whether to let the students fully understand why the first two numbers were added first or the last two numbers were added first when adding three numbers, and the intrinsic reason why the sum did not change. - At the same time, he also had to consider the breadth of the teaching content and whether it expanded the connection between addition and deduction and real life or other subjects. For example, through the price calculation in the shopping scene to reflect the widespread application of addition and substitution in life, or the addition and substitution operations involved in scientific experiment data processing. ** 3. Teaching methods and strategies ** 1. ** The effectiveness of teaching methods ** - This paper analyzed the effects of teaching methods such as lecture method, demonstration method, and inquiry method in addition and substitution teaching. For example, when explaining the vertical calculation of integral addition, whether the teaching method clearly conveyed the calculation steps and carry rules; in the addition and substitution of scores, whether the demonstration method (such as using graphs to represent scores) helped students understand the calculation theory. - Does the inquiry method give students enough space to learn independently? For example, when exploring the law of addition, should the students be guided to discover the law on their own instead of directly telling the result? 2. ** The rationality of teaching strategies ** - Whether or not a variety of teaching strategies are used to meet the needs of students with different learning styles. For example, for visual students, whether they used teaching resources such as graphs and charts, and for kinaesthetic students, whether they arranged some practical activities (such as using a stick to perform addition and multiplication). - Consider the role of teaching strategies in classroom management. For example, whether the grouping strategy of group cooperative learning was reasonable, whether it could avoid the phenomenon of individual students "free riding", and at the same time promote cooperative learning between students. ** 4. Student performance and individual differences ** 1. ** Overall student performance ** - It summarized the overall performance of the students in the addition and substitution class, including class participation, homework completion, test results, and so on. For example, whether most students answered questions actively in class, how accurate their homework was, and the distribution of scores in the addition and substitution section of the exam. 2. ** Coping with Individual Disparities ** - To analyze how to treat the individual differences of students in the teaching process. For students with strong learning ability, whether they were provided with expansive learning tasks, such as guiding them to explore more applications of the law of operation in simple calculations after mastering the basic addition and deduction operations; for students with learning difficulties, whether they were given enough attention and guidance, such as whether they were given individual guidance and intensive exercises for students who were easy to make mistakes in the calculation of decimals. ** 5. Problems in the teaching process and improvement measures ** 1. ** Problems ** - Find out the specific problems in the teaching process. For example, the teaching schedule was unreasonable, resulting in some important content being explained in a hurry; or the teaching resources were not fully utilized, such as the animation demonstration in the multi-media class did not play a very good role in assisting teaching. - The reason for the problem could be that the teaching design was not perfect enough, the students 'learning situation was not estimated enough, or the teacher's own teaching ability needed to be improved. 2. ** Modification measures ** - According to the existing problems, specific improvement measures were proposed. If it was a problem of teaching time arrangement, he could re-plan the teaching process and reasonably allocate the time of each teaching link. If it was a problem of the use of teaching resources, he could re-select or produce more effective teaching resources, such as making more intuitive teaching animations of score addition and deduction. - He thought about how to prevent similar problems from happening again in future teaching, such as strengthening the rehearsal and evaluation of teaching design to continuously improve his teaching ability. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Who has a novel similar to the addition and substitution of the second world?
There were novels similar to "Adding and Subtracting in a Middle Ages World" 1:"Daily Entertainment: A Glimpse of Light and Shadow." Author: Xi Xi Yan Qing 2."The Richest Man on Earth Begins in the Primitive Wilderness." Author: Happy Popcorn 3."VR Game Instance Dungeon Begins From Beating Up Intruder Dogs", Author: Kitaguipu 4. Yunhua Yao Ji, Author: Qi Zong 5:"I Cultivate a God in Tokyo", Author: I Want to Shabu Hotpot Chapter 6: Dark Card God, Author: Dream of Egg-Fried Rice 7:"After I Devoted myself to Criticize the Supervisor, I Have a Baby", Author: Xiaolou Girl 1 The following is a detailed introduction of these novels: 1."Japanese Entertainment: A Glimpse of Light": Come to Yuewen's website to read more of my works! 2."The richest man on Earth starts from the primitive wilderness": War is terrible. It can destroy everything. If human civilization were to disappear and return to the era of drilling wood to make fire, gathering and hunting for a living, would you still be able to survive? Entering the wilderness, our global competition has begun! They ventured deep into the Amazon rainforest, survived the storm on rafts, and escaped from the death strangulation of giant pythons... They would go back to the place where Su Wu was herding sheep, feel the cold wind of-50 degrees Celsius in Siberia, and fight with the wild wolves that were rushing towards them... The canoe sailed across the ocean, and not only did it face the surging waves, but when you wanted to eat fish, the great white shark opened its bloody mouth and bit you… "What happened to the animals that tried to bite you?" asked the reporter. Lin Zheng: "The protein has turned into an amine acid, and it has injected…powerful energy into my body!" The story had to start from the North American continent, hunting, gathering, fishing, catching turkeys, smelting copper, forging iron, and making porcelain… In 30 days, they had embarked on a path of civilization that the Native Americans had never taken in tens of thousands of years. At first, every step was frightening. There were so many snakes in the valley! 3."VR game dungeon starts from beating up the invading dog." What? Am I the only one who can see the light blue jellyfish in the game? The rich and beautiful woman gave me a USB drive to help me become a max level NPC! There was such a good thing? An Zhui had transmigrated into a Level 2 security NPC of Mythology VR technology. His daily routine was to enter the game dungeon: Using a BUG to cheat. Buff bonus, To load the program's plug-in and refresh the skill. He was a tool who worked hard to maintain the order of the game. After a game dungeon invasion incident, he got to know the ferocious seniors: an NPC who liked to smash people with the ball-tomboy; The NPC with the unconventional love brain-Centipede Scar Lisa; Deep well ice aesthetics master-Clown Girl·Mourning Sauce; Unstable and capricious-Team Leader Old K. …… 4.<<Yunhua Yao Ji>> I am a demon exorcist that is not very popular. However, his ability was not weak. Just when I thought that I was going to spend my life calmly slaying demons. I lost my blade. A demon slayer losing his blade is no different from losing his life, but I found another blade. This saber had a human-shaped saber spirit. The following is the story of how I brought the idiotic demon servant and the human-shaped saber spirit with facial paralysis (crossed out) around the world to eliminate demons. Why did he have to exterminate demons? It was not a matter of national hatred. It was purely a matter of profession. This book does not cultivate immortality. 5."I Cultivate a God in Tokyo": Travel through Tokyo, Japan, and become a shrine priest. He looked at the shrine that had no shrine girls, no believers, and no future. As well as the obedient, ignorant, and weak gods who only knew how to hug thighs. Shiroki could only sigh helplessly and stand up to face the evil spirits of Tokyo. "I really like something Ksitigarbha Bodhisattva said." "If hell is not empty, then it is not empty." 6. Dark Card God: A little bit of light in the apocalypse. Darkness and turmoil sit together. A young man with a shocking secret rose in the apocalyptic era. Was it the collision of machinery and technology, or the impact of cold weapons and hot weapons? The young Su Bin had awakened the card system and had given birth to the strongest buff. He had risen in the midst of turmoil and had turned the world upside down. 7:"After I Dedicate My Body to the Supervisor, I Have a Baby": A court official under one person VS a delicate beauty who hides secrets Feng Xiao 'er had married the most treacherous official of the current dynasty. She had been scheming step by step, but he had seen through her every step. She was originally a top-notch assassin in the martial arts world. For the sake of information, she served tea and water to the superintendent, massaging his shoulders and legs. She was pitiful and humble. After gaining the eunuch's trust, she began to put her arms around the eunuch's shoulders and wanted to be good sisters with him. One night, Xiao Qi pressed her against the corner of the wall and said evilly. "Woman, submit to our family. We will give you the power to be above everyone else." "Don't mess around." She hammered his chest with her small hand. He was even more disdainful. How could a eunuch take advantage of him? In the end, she wanted to cry but no tears came out of her eyes.
Reaction Formula of Substitution Reaction for the addition reaction of organic substances
Additional reaction: - The addition reaction of ethene and Bromine: <<CH2 = CH2 + Br2> - The addition reaction of ethene and hydrogen bromidate was as follows: <CH2 = CH2> - Under certain conditions, addition reactions could also occur between ethene, hydrogen, and water. Since the chemical properties of ethyne (carbon-carbon triple bond) were similar to that of alkene (carbon-carbon double bond), similar addition reactions could also occur. - The aromatic ring can undergo an addition reaction with hydrogen (in the presence of a catalyst such as Ni). - Aldol groups can undergo a reduction reaction (addition reaction), such as: <anno data-annotation-id ="00000000 - 4c00 - 4c00 - 8c00 - 9c00 - 9c000b000000"> CH3CH20H </anno>. Substitution reaction: - The substitution reaction between methane and Cl2: CH4 + Cl2. - The substitution reaction of the aromatic ring: For example, the substitution reaction with the aromatic group using FeBr3 as a catalyst; the nitration reaction with the aromatic group using concentrated sulfuric acid under heating conditions (the hydrogen on the aromatic ring is replaced by the nitrogen group). - The substitution reaction of the halated carbon was as follows: <<CH3CH2Br2>+<NaBr2>>. - The substitution reaction of alcohol: <CH3CH20H>+<br>> longrightarrow <CH3CH2br>+<H2O>> - The ester's cleavage reaction (which can be seen as a substitution reaction):<CH3COOCH2CH3 + H2O> <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Reflection on the teaching of addition and substitution of numbers within ten thousand
The following are a few aspects that may be involved in the reflection of addition and substitution teaching: ** 1. Teaching methods ** 1. ** Diverse algorithms and independent exploration ** - It was important to give the initiative to the students when teaching addition and substitution of numbers within ten thousand, so that they could explore the calculation method independently with the help of their existing knowledge and experience. For example, for mental arithmetic and vertical calculation, don't design overly guiding questions to avoid bringing students into the default method. Let the students do the math by themselves and share the results in the group so that they can experience the success of independent learning. - In the teaching of vertical calculation, students were also allowed to try it out on their own, and then they could exchange and demonstrate. This method could effectively expand the students 'thinking and promote the exchange of algorithms. 2. ** Situation Creation and Question Guidance ** - Creating a suitable situation was very helpful to teaching. For example, the introduction of addition teaching from the pictures of the World Exposition could arouse the enthusiasm of students to learn. At the same time, it allowed students to find mathematical information in the situation and experience the connection between addition and life. - In the process of teaching, the social practice situations such as the different ticket prices of different means of transportation were used to let students experience the significance of deduction in comparison and feel the connection between deduction and life. Moreover, it allowed students to discover, raise, and solve problems independently in specific situations, experience independent thinking, take the initiative to explore, report and communicate, and so on. Finally, the teacher would focus on introducing a main method that would help students form a representation and experience mathematical ideas. - However, there might be problems in the creation of situations, such as the data processing in some situations that might make students confused. For example, in a teaching situation where 500 bottles were given once, 520 bottles were given in the first two weeks, and the remaining 20 bottles were ignored in the teaching. This may cause students to have doubts and need to better deal with the data logic in this situation. 3. ** Estimated Teaching ** - The cultivation of estimation ability was part of the teaching. However, there were some puzzles in the teaching. For example, the format of the estimation formula was not clear. It was not known whether the students should directly write the approximate calculation result (such as 190 + 220 = 410) or use the half-text and half-algorithm format (such as 192+219 is approximately equal to 190+220 = 410). - Students had a biased understanding of estimation, and there was a situation where they estimated for the sake of estimation. Some students would first calculate the accurate answer and then find an approximate number as an estimate, and most students would not use the estimation method to test the rationality of the calculation results. ** 2. Student learning ** 1. ** Cultivation of computing ability ** - In the cultivation of computing ability, one must pay attention to correct, flexible, reasonable, and concise operations. For example, in the process of solving problems, students should be allowed to choose the calculation method flexibly according to the actual situation. For example, in the situation where estimation and precise calculation were needed, students should improve their computing ability. - In teaching, open questions were designed to allow students to solve the problem in different ways (multiple solutions for one question). In the observation and comparison of different methods, they chose a reasonable and concise calculation path. - However, there might be insufficient practice in actual teaching, resulting in students not being able to consolidate their knowledge well and affecting the improvement of their computing ability. 2. ** Attention to Individual Students ** - In the teaching process, the individual differences of the students should be fully taken into account, including their acceptance ability and psychological characteristics. For example, in the teaching of multiplication (such as 300 - 116) where there are zeros in the middle of the minuend, it may be because the students do not have a good grasp of the learning situation, and the situation of individual students listening to the class and mastering the knowledge is not ideal. When students explore the calculation process (such as demonstration 300 - 116), the teacher should give enough time for the students to think. They should not be in a hurry to explain. They should face all the students and let the students inspire each other to find a solution to the problem. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Self-made teaching plan and reflection on the application of addition and substitution
#<Self-made teaching plan for big class of addition and substitution application questions> ##1. Teaching objectives 1. Let the children learn how to write their own addition and substitution problems. 2. Cultivate children's thinking flexibility, agility, logic and oral expression. 3. To develop the child's visual ability and judgment. ##2. Teaching preparation 1. Arithmetic cards, a slide, a number of flowers (or other small items), a drum, a picture (containing a different number of animals or objects), and a set of numbered cards for each person. 2. Ask the parents to take the children to buy things in advance so that the children understand the process of buying and selling. Prepare 10 Math Books for Children, 10 calculation cards, and 10 fruit cards. ##3. Teaching process ###(1) Introduction of revision 1. Through games (such as Sunshine Express), review addition and multiplication within 10. For example, if the teacher said that the calculation was "2 + 3 =", the child would answer "5". 2. Show a slide, the content is some addition scenes, such as children playing on the playground, monkey activities on the grass, the number of trucks in the parking lot, etc., let the children answer the calculation and the number according to the picture. You can use the method of answering first, group competition, or collective answer. ###(2) Adding applied problems 1. ** Create a scenario and write a question ** - Ask the two children to come to the front. The teacher will give two flowers to one child and three flowers to the other child. Then ask,"What is the teacher doing?" Following that, he used the two numbers "2" and "3" to demonstrate an addition problem."The teacher gave the children red flowers. First, he gave the children two red flowers. Then, he gave the children three red flowers. How many red flowers did the teacher give in total?" Guide the child to list the calculations. 2. ** Explain how to write questions ** - By repeatedly asking,"What's the thing in this question? What were the two known numbers? What was the last question?" Explain to the children the basic methods and steps of making addition application problems. ###(3) Subtraction word problems teaching (can be compared to addition word problems teaching steps) 1. ** Create a scenario and write a question ** - For example, if the teacher showed five apples and took away two, he would ask the child,"There were originally five apples. Now that two are taken away, how many apples are left?" Guide the child to write the formula "5 - 2 = 3". 2. ** Explain how to write questions ** - Similarly, by asking,"What does this question talk about? Which two numbers do you know? What's the problem?" To let the children understand the composition of the multiplication word problem. ###(4) Consolidating Practice 1. ** Training with supplementary questions ** - For example, if there were originally three planes in the sky and four more planes flew over, the teacher would first make up the questions, then inspire the children to think whether it was complete, and guide the children to ask the question,"How many planes are there in the sky?" He also asked the child to explain the problem completely and write down the formula. 2. ** Practice of drawing pictures and writing questions ** - Show the picture (if there are ducks in the picture, the size, color and position are different). Ask the child to write an addition or deduction problem according to the picture, and use the card to arrange the calculation. 3. ** You make it up, I make it up ** - Two people in a group, one person wrote the questions, and the other set the calculations. ###(5) Organizing the game-pass the ball and make up application questions The child listened to the drumbeat and passed the ball. When the drumbeat stopped, the child who got the ball ran to the front and used what he usually saw, heard, or did to make up an addition or deduction application question for everyone to listen to. If he made it right, the teacher would reward him with a small red flower. The game was repeated. ###(6) Evaluation Teacher: Today, we learned how to write addition and substitution problems. There are three conditions for writing a problem. First, you have to say one thing. Second, you have to have two numbers. Third, you have to have a problem. Please use your brains to come up with more and better problems when you go back. ##IV. Reflection on Teaching 1. ** Children's learning situation ** - In the whole teaching activity,"application questions" were difficult for the children to understand and master. Some of the children performed well in the creation and solution of the addition problem, and they could understand the concept of adding two parts to get a total number. However, in the deduction problem, some children had difficulty understanding the known total number and one part to find the other part. For example, in a deduction problem involving a specific scene, such as taking a part of a group of items to find the remaining part, the child may confuse the relationship between quantity and quantity. 2. ** The effectiveness of teaching methods ** - Scenarios and games could better attract children's attention and increase their participation. For example, by giving flowers to children and showing the change in the number of apples, children could intuitively feel the relationship between numbers, which would help them understand the structure of the application questions. In the game segment, the method of passing the ball to make up the application questions stimulated the children's sense of competition and prompted them to think and create actively. However, children with weaker comprehension abilities may need more one-on-one guidance. 3. ** Combination of life experience and teaching ** - It was helpful for children to experience the process of buying things in advance. Many children could apply the buying and selling relationship in shopping to the creation of application questions, such as "I have 5 yuan, but I bought a 3 yuan toy. How much money do I have left?" This shows that connecting mathematics education with real life can enhance children's understanding and application of mathematical concepts. However, he could still further explore other scenes in life, so that children could have more material to create. 4. ** Modification measures ** - In future teaching, more different types of practice methods could be added, such as group competition, mutual error correction, etc., to strengthen children's understanding of applied problems. For children who had difficulty understanding, they could design some simple exercises and guide them step by step from the most basic number relationship. At the same time, continue to strengthen the connection between mathematics education and life, encourage children to observe mathematical phenomena in life, and improve their ability to use mathematical knowledge to solve practical problems. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Wedding planning, photography or photography is better
Photographer and videographer had different characteristics and advantages, and choosing which one was better depended on many factors. Photographs presented the wedding scene and details in a static manner. It could help the couple capture the beautiful moments of the wedding scene. The images were often more soulful, and the photo form was convenient for sharing on social platforms (such as friends). The camera was a video recording, which recorded the wedding scene and details in a more realistic and vivid way. It could present a comprehensive and realistic dynamic picture of the day. When the wedding was over, the visual sense was more intuitive and impactful, allowing the newlyweds to clearly feel the touching moment on the wedding day again. If the budget was limited, they might have to choose according to their preference for recording weddings. If you want to record life beautifully, especially if you want to relive the overall dynamic atmosphere of the wedding day, you can choose photography. If you want to share wonderful moments on social platforms, you can choose photography. If the budget was sufficient, it would be best to choose both. With aerial photography, the image would be more comprehensive. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
How to write the best way to sum up and reflect on the teaching of addition and substitution
The following is a summary and reflection on the teaching of addition and substitution: ** I. Teaching summary ** 1. ** Achievement of teaching objectives ** - Knowledge and Skills: Clearly describe the student's knowledge of addition and substitution (such as addition and substitution of whole numbers, fraction addition and substitution, or decimals addition and substitution, etc., depending on the actual teaching content). For example, whether he could accurately calculate all kinds of addition and substitution formulas, whether he could skillfully use the addition and substitution operation law (if it was involved) to perform simple calculations, and so on. - Method and process: summarize the process of thinking, inquiry, reasoning, etc. that students have experienced in the process of learning addition and deduction. For example, in the teaching of addition and substitution of different decimators, whether the students could transform the problem into the knowledge they had learned to solve it through general fraction and other methods, and whether they understood the calculation theory behind the operation. - Emotional attitudes and values: measure the students 'interest in learning addition and deduction, self-confidence, and other changes in emotional attitudes. For example, whether they were passionate about learning mathematical operations, whether they dared to try to solve addition and substitution problems, and so on. 2. ** Teaching content analysis ** - Key content: emphasize the key parts of addition and substitution teaching, such as the application of the commutative law of addition, the combination law in the addition of whole numbers, or the processing of the numerator in the addition and substitution of scores. Analysis of the processing methods of these key contents in the whole teaching process and the students 'mastery. - Difficulty Breakthrough: For the difficult points in addition and substitution teaching, such as the understanding of the calculation theory in addition and substitution of different decimators (the different decimators need to be converted into the same decimators), the problem of digit alignment in addition and substitution of decimals, etc., explain the teaching methods used to break through these difficulties, as well as the students 'performance after breaking through the difficulties. 3. ** Teaching Method Usage ** - The effectiveness of teaching methods: evaluate the teaching methods used in addition and substitution teaching, such as lecture method, demonstration method, inquiry method, etc. For example, when teaching the law of integral addition, whether it would help students understand the law of addition through specific life examples (such as shopping and accounting); in the process of exploring the addition and substitution of scores, whether the group cooperation method stimulated the students 'learning enthusiasm and improved their computing ability. - The innovation of teaching methods: If some innovative teaching methods are used in the teaching process, such as the use of mathematical games, multi-media resources, etc. to teach addition and multiplication, the effect of these methods on the improvement of the teaching effect should be described. ** 2. Reflection on Teaching ** 1. ** Reflection on the students 'learning situation ** - Individual differences: Think about the differences in the performance of different students in addition and deduction. For example, for students with strong learning ability, whether the teaching content is challenging enough, and for students with learning difficulties, which aspects are not given enough support? For example, in the teaching of decimals addition and substitution, some students may often make mistakes in dealing with decimals. Is there enough guidance for this situation? - Learning feedback: analyze the feedback from students in class exercises, homework, tests, and other aspects. If a student had a high error rate in a certain type of addition and substitution operation (such as the fraction operation in fraction addition and substitution), he would reflect on whether it was caused by unclear teaching content or insufficient practice. 2. ** Reflection on the teaching process ** - Teaching segment design: review the various segments of addition and substitution teaching, such as introduction, new teaching, practice, summary, etc. For example, whether the introduction phase could effectively attract students 'attention and stimulate their interest in addition and substitution learning; whether the knowledge points in the new teaching phase were clear and orderly; whether the questions in the practice phase were targeted and hierarchical, and whether they could meet the needs of students at different levels; whether the summary phase could help students sort out the knowledge system of addition and substitution. - Time allocation: Consider whether the time allocation for each teaching content in addition and substitution is reasonable. For example, did he spend too much time teaching the addition law, resulting in insufficient practice time for the subsequent deduction? 3. ** Reflection on Teaching Resources ** - Use of teaching materials: Reflect on whether the use of teaching materials is sufficient and reasonable. For example, whether the examples and exercises in the teaching materials were effectively used, and whether the content of the teaching materials was supplemented or adjusted according to the actual teaching situation. - Extra-cursory resources: If extra-cursory resources are used in addition and substitution teaching, such as mathematics extra-cursory reading materials, online mathematics course resources, etc., you should reflect on the effect of the use of these resources and whether it helps to improve the students 'addition and substitution ability. 4. ** Modification measures ** - According to the above reflection, specific improvement measures were proposed. For example, if it was found that students had difficulty understanding arithmetic in addition and substitution of different decimators, more visual demonstration could be added, such as using graphics (auxiliary tools such as ten-grid matrix) to help students understand. If the time allocation of teaching was unreasonable, the time arrangement of each link should be re-planned. If there was insufficient support for students with learning difficulties, individual tutoring plans could be formulated. When writing the summary and reflection of the addition and substitution operation teaching, it is necessary to analyze all aspects of the teaching process in a comprehensive and objective manner in order to continuously improve the teaching quality and help students better master the knowledge of addition and substitution operation. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Elementary school fourth grade second volume mathematics addition and substitution calculation
In the second volume of the fourth grade mathematics addition and substitution calculation, there were some important contents: ** 1. Laws of Operations ** 1. ** Nature of Subtraction ** - Subtracting several numbers from a number in a row was equal to the sum of this number minus these deductions. It was expressed in letters as a - b - c=a-(b + c). For example, when calculating [5.17-1.8 - 3.2], the formula could be converted to [5.17-(1.8 + 3.2)=5.17 - 5 = 0.17]. - In the reverse calculation, a-(b + c)=a - b - c). During this process, one must pay attention to the change of symbols. Many students tend to forget to change symbols during the reverse calculation. - There was also the commutative law of substitution, which was expressed as a (a-b- c= a-c- b). 2. ** Moving with Symbols in Same-Level Operations ** - When there was only addition and substitution in the equation (which belonged to the same level of operation), it could be moved with a sign. For example, when calculating the addition and deduction of an equation, such as <79+187 - 187+21>, you can move <187>> to the front, with the minus sign in front of it,<79>> to the back, with the plus sign in front of it, it becomes <79 - 187+187+21>, which makes it easier to calculate. It was also applicable to the addition and reduction of decimals. For example,"5.82+0.18 - 3.6" could be moved to the back of "5.82" with the plus sign in front, and "3.6" could be moved to the back with the minus sign in front, becoming "5.82+0.18 - 3.6=(5.82 + 0.18)-3.6 = 6 - 3.6 = 2.4". 3. ** Rules for Removing and Adding Brackets ** - When removing or adding parenthesis, if there was a "+" in front of the parenthesis, there was no need to change the sign; if there was a "-" in front of the parenthesis, the sign had to be changed."+" became "-","-" became "+". For example,<9.64-(3.64 + 3)>, after removing the parenthesis, becomes <9.64 - 3.64 - 3=6 - 3 = 3>. ** 2. Error-prone Points in Calculation ** 1. Be careful not to be careless when calculating. Be careful not to count addition as deduction or deduction as addition. 2. Remember to add one when carrying out addition, and remember to abdicate and subtract one when abdicating. ** 3. Calculation of decimals ** 1. He had to pay attention to the alignment of the decimals, and then he had to do the calculation according to the method of addition and substitution of the whole numbers. For example,(20.67-1.48 = 19.19\)，\(18.88 - 16.03=2.85\)，\(15.35 - 9.05 = 6.3),(3.26+20.2 = 23.46),(4.23+1.45 = 5.68),(20.85 - 13.3 = 7.55),(4.21+12.74 = 16.95),(18.62 - 17.01 = 1.61), and so on. 2. The simple operations of decimals were also applicable to the above operational laws, such as the nature of the substitution, moving with symbols, and so on. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>