3. have discovered, galaxies, universe　

2. found life, planets yet　

A: Have you _____ Jim these two days?

B: No, he’s _____ to Japan to see his daughter.

A: Has he ever been there ______?

B: Of course. He lived there before he ______ here.

A: Have you still not _____ a letter from him?

B: Yes, I’ve just ______ a letter _____ him.

A: What ______ he say?

B: He said that he ______ a good time ______ would stay there for three weeks. Then he would come back.

单元练习答案

5. Her mother has been to Hong Kong several times. (就画线提问)

　　 　　______　 _______　 ______ has her mother been to Hong Kong?

4.　　 I came here two days ago. ( 同义句)

I ______　 _______ here _______ two days.

3.　　 To understand the problem is very difficult. (用it 作为形式主语)

______　 ______ very difficult _______ understand the problem.

2.　　 Have you got a letter from Lucy? (同义句)

Have you ______　 ______ Lucy?

1.　　 They heard a message from a spacecraft. (用just改为现在完成时态形式)

They _____ just ______ a message from a spacecraft.

10.　 The bus _____ (go) . It left twenty minutes ago.

9.　　 Many girls are good at ______(make) things.