7.We have built a rock fence around the house.
-> A rock fence has been built around the house.
8. I didn't understand the lesson.My friends didn't understand it,either.
-> I didn't understand the lesson. Neither did my friends.
9.Our teacher don't allow us to talk in class.
-> Our teacher don't let us talk in class.
~ Chúc bn hk tốt!~
~ Nếu đc thì cho mk trả lời hay nhất nha!~