I

20. Have you ever been in Ho Chi Minh yet?

- No, I haven't been there yet. But my parents have been there twice this years.

21. She's got the best voice I have ever heard.

22. Since when have you learnt English?

- I have learnt it since I was a girl of twelve.

23. They have done nothing since they got up.

24. I have written two letters already.

25. I flied over Loch Ness last week.

- Have you seen the Loch Ness monster?

27. This is the first time the children have traveled by planed.

28. Have you been here before ?

- Yes, I spended my holidays here last year.

29. Has the newspaper come?

- yes, Ann is reading it.

30. Shakespeare has written a lot of plays.

II. 

1.

-I haven't known her for 2 years.

-Have you known her for 2 years?

2.

- Tom hasn't been to Hanoi before.

- Has Tom been to Hanoi before?

3. 

- We haven't lived for 10 years.

- Have you lived for 10 years.

4. 

- They haven't worked with my father recently.

- Have they worked with my father recently?

20. Have you ever been in Ho Chi Minh yet?

No, I haven't been there yet. But my parents have been there twice this years.

21. She's got the best voice I have ever heard.

22. Since when have you learnt English?

I have learnt it since I was a girl of twelve.

23. They have done nothing since they got up.

24. I have written two letters already.

25. I flied over Loch Ness last week.

Have you seen the Loch Ness monster?

27. This is the first time the children have traveled by planed.

28. Have you been here before ?

 Yes, I spended my holidays here last year.

29. Has the newspaper come?

yes, Ann is reading it.

30. Shakespeare has written a lot of plays.

1.I haven't known her for 2 years.

Have you known her for 2 years?

2.Tom hasn't been to Hanoi before.

Has Tom been to Hanoi before?

3. We haven't lived for 10 years.

Have you lived for 10 years.

4 . They haven't worked with my father recently.

Have they worked with my father recently?