Our plan is to plant 50 trees. And we have planted half of them 　　　.

— ________ have you learned to play the piano?— ________ five years ago.

Mrs Smith lives next to us. She is really a good _______, because she always helps us.

He is ______fat because he eats ______ meat.

 The meeting will begin ________ 4:30 this afternoon. Don’t forget it.