Bài 1 :

D  B  C C D A D B C C.

Bài 2 :

3.Since

4.For

5.Since

6.For

7.Since

8.For

9.Since

10.Since

Bài 3

1. have lived---2.have worked---3.has read---4. have known---5.haven't seen---6.haven't worked---7.have bought---8.haven't planned---9.have you been---10.has written---11.have you been---12.hasn't started---13.has he spoken---14.hasn't had---15.has just catched---16.has already invited---17.has made---18.has lost---19.have just cleaned---20. have given up-------------

 Bài 4 :

1. I have had this computer for 3 years.

2. They have lived in Da Lat since last year.

3. She has been happy since she had the mobile phone.

4. We have learnt French for a month.

5. She has worked in this school since 2012.

6. I have used this computer for 5 years.

7. The washing machine has stopped working since this morning.

8. They have known her for a long time.

9. He has read this novel since 9 o' clock.