1. They  have never eaten Mexican food.

2. Hoa has walked in the rain many times. She loves it.

3. I have never seen such a big flower.

4. we  haven't visited Nha Trang.

5. I  have read that novel three times.

6. He has never met her before.

7. The zoo isn’t far from here. I have walked there three times.

8. If  we  don't economise on electricity there will be power cuts. ( Câu điều kiện ) 

9. I hope he will finsh his home work before we get back

10. If we sit too far away from the screen I  won't be  able to see the film ( Câu điều kiện )

11. Listen to those people! What language they are speaking ( HTTD )

12. Where do you come from Finland 

- I come from Helinki. But I haven't lived  there since I was ten years old.

13. Look at the sky ! It is rainning ( HTTD )

1. have never eaten.

2. has walked.

3. have never seen.

4. haven't visited.

5. have read.

6. have never met.

7. have walked.

8. don't economise.

9. will finish; get.

10. won't be.

11. are speaking.

12. do you come; come; haven't lived.

13. is raining.