8.　　 The boy tried _____(climb) the tree, but he failed.

7.　　 Don’t forget _____ (close) the door when you leave home.

6.　　 The girl ______(go) to visit the city if it ______ (not rain) tomorrow.

5.　　 ---______ you ______ (have) your supper?

---Yes, I have.

4.　　 What do you think Li Ping_______(do) right now?

3.　　 ---Where is my friend? ______you _______ (see) her?

---Yes, I ______ her three minutes ago. But she ______(go) to the post office. I think she ______(be) back soon.

2.　　 ---_____you ______(return) the book to the library yet?

---Yes, I _____. I ______(return) it yesterday afternoon. The book ______(be) very interesting.

1.　　 ---What _____ she ______ ( do ) last Sunday?

---She ______(listen) to the radio.

5.　　 为什么没有人从别的行星上给我们发送信息呢？

Why has ______　 _______　 _______ other planets _______ us a message?

4.　　 弄清楚宇宙有多大是困难的。

It is hard ______　 _______　 _______ large the _______ is.