Corrected sentences
1) Once upon a time there was a poor miller who had three sons. When the miller died, the oldest son inherited his father's mill, the second son got the donkey, and the youngest son got only a cat.
2) Without delay, Puss set off to hunt. He caught two fine rabbits and took them to the king's palace. The guards couldn't believe their eyes when they saw a cat in boots carrying a bag walking by, so they let him inside.
Simple explanations (for a 7-year-old)
- Make who is being talked about clear: In sentence 1 I changed "When he died" to "When the miller died" so it is clear we mean the father, not one of the sons.
- Use words kids know: I used "oldest" instead of "eldest" because "oldest" is a word you hear more often.
- Show ownership with an apostrophe: "father's mill" uses an apostrophe to show the mill belongs to the father.
- Make the action clear: In sentence 2 I added "saw" so it reads "when they saw a cat..." That tells us the guards noticed the cat.
- Use a little extra word for emphasis: "only a cat" tells us the youngest son did not get anything else.
- Commas and pauses: The comma after "When the miller died," and after "Without delay," helps the sentence sound right when you read it aloud.
If you want, I can explain any of these points with more examples or rewrite them in an even simpler way. Would you like that?