【小题1】I was writing a letter when my mother got home. (对划线部分提问)
What were return to you doing when your mother got home?
【小题2】Could you give the book back to the school library tomorrow? (改为同义句)
Could you if/whether was the book ask for the school library tomorrow?
【小题3】“Are you mad at your sister?” Mary said to me. （改为间接引语）
Mary asked me I mad at my sister.
We should What were the police return to help when we are in trouble.