I have no idea as I don't know the 'day 134 word story' itself.
Since we don't have the actual 'day 416 word story' here, it's really difficult to figure out the theme. If it's a story about a person's struggle and how they overcome difficulties, the theme could be perseverance. Or if it's about two people falling in love, the theme would be love. But without seeing the story, it's all just guesswork.
I have no idea as I don't know the 'day 252 word story'.
There's no way to tell for sure without knowing the story. It could be about friendship, adventure, or discovery.
I don't know the actual 'day 275 word story', so it's hard to say. It could be about love, adventure, or mystery. There are so many possible themes.
Another possible theme could be change. Day 260 might mark a significant change in someone's life. For instance, a person who has been living in a small town all their life decides to move to a big city on day 260. The story could revolve around how they adapt to the new environment, the new people they meet, and the new opportunities that come their way. It could show the challenges and the rewards of this big change.
It could be friendship. Many short stories revolve around the theme of friendship.
One possible theme is 'redemption'. Suppose in the story, a person has made mistakes in the past. Over the course of 708 days, they strive to make amends and by the end of day 708, they achieve redemption. They might have wronged someone they loved and through a series of events across these 708 days, they are able to ask for forgiveness and start anew.
Perhaps the theme is about discovery. If new words were added each day, it might be like the discovery of new ideas or elements in a story. The story could be about a character exploring a new world, and each day's word represents a new discovery within that world. For instance, if one day the word was 'mystery', then a mystery element could be introduced into the story's plot.
Since I don't know the details of 'day 209 word story', it could be any theme. It might be a love theme if the word was something like 'heart' or 'affection'. Or it could be a adventure theme if the word was 'journey' or 'explore'.
Since we don't know much about the 'day 420 word story', the theme could be quite diverse. It could be a story centered around nature if the writer spent a lot of time outdoors during those 420 days and was inspired by the beauty of the natural world. It might also be a story about perseverance, especially if the writer faced difficulties during the writing process or in their life during that time. Or it could be a humorous story, perhaps the writer used the 420 days to come up with comical situations and characters.