Academic Master

Dong Li let out a long sigh and rubbed his eyebrows.

Seeing her brother's bad expression, Dong Huang lowered her head and said, "Brother, I'm sorry. Xiao Huang was so stupid and let you down."

Dong Li looked at his sister and found that her eyes were red and there were tears on her eyelashes. He can't blame her. After all, she had been malnourished since birth. So it's normal if her brain develops slower than other children.

He patted her back gently and encouraged her, "Don't worry. If Xiao Huang doesn't understand, Brother will explain it to you. As long as you work hard and don't give up, you will definitely be able to solve this problem."

Then he picked up his pencil and a piece of recycled paper and began to explain the problem to his sister. Although this question is very simple for Dong Li, it is not something that a second grader can solve.