英语一些解释句子

英语一些解释句子
1.I left my hometown three years ago.
2.I could play the piano （at the age of ）seven.
3.we were sure that he （could）work out the problem.
4.This is the first time that I have met him.
5.I （wonder）when he will （leave for） America.
6.He has had a bad cold （since the day before yesterday）.
7.My grandpa often takes a walk after supper.
8.I haven't read this book .Susan hasn't ,either.
9.My pan friend went to Shenzhen last year.And he is still there .
10.Our English teacher has been in our school foe 6 years.
不是解释句子的意思，解释就是改写句子