Choose the best answer.
 1. This is the most interesting novel _______________ 
            A. I’ve read               B. I had read               C. I’ve never read                  D. I’ve ever read 
2. I haven’t seen you _______________ 
           A. since a long time             B. for ages              C. ages                 D. for long existence 
3. It _______________ every day so far this week. 
          A. rained                B. has rained                   C. rains                    D. is raining 
4. I _______________any letter from him yet. 
          A. haven’t received                B. will receive             ,km  vcfd esw3szC. don’t receive D. didn’t receive 
5. We _______________to Dalat several times. It’s a foggy city. 
          A. were                       B. have been                    C. were being                 D. had been 
6. I haven’t met him since he _______________school.
          A. left                  B. was leaving                    C. had left                    D. was left
7. My uncle _______________on this farm since he was 20.
          A. has worked              B. have worked                   C. worked                 D. was working
 8. He _______________London 2 years ago and I _____________him since then. 
         A. left/ hadn’t seen       B. left/ haven’t seen       C. was living/ haven’t seen     D. left/ didn’t seen
 9. By the time Tom got back, Peter _______________
         A. have gone                B. went                 C. will go                   D. had gone 
10. She _______________in Hue for twenty years. 
        A. lives                  B. has lived                    C. lived                      D. will live 
11. It is the most exciting film I _______________ 
        A. never saw             B. ever saw                  C. had ever seen                 D. have ever seen 
12. They have been in love with each other _______________ they were young 
       A. while                 B. until                       C. for                          D. since 
13. I _______________the money from him yet. 
       A. haven’t received              B. don’t receive                   C. will receive               D. am receiving 
14. I _____________ (not see) my brother for 5 years. 
       A. hasn’t seen                  B. don’t see                         C. aren’t see                       D. haven’t seen 
15. How many times _______________ there so far? 
      A. have you been               B. would you be                C. were you                      D. had you been
16. It’s at least a month since _______________Tom. 
      A. I last seen                     B. I last see                     C. I have last seen                 D. I last saw 
17. We _______________ almost every lesson in this book so far.
       A. Study                       B. studies                       C. has studied                     D. have studied 
18. We _______________that television program.
       A. never watch            B. not never watch          C. have never watched        D. has never watched
 19. Up to then, I _______________such a big fire. 
       A. have never seen            B. had never seen             C. never seen                 D. never see 
20. I _______________her since I _______________a student. 
       A. know/ am           B. knew/ was            C. have known/ am                 D. have known/ was
 21. _______________ get tired of answering the same questions every day? 
       A. Have you ever              C. Had you ever                  B. Do you ever               D. Are you ever 
22. She _______________working on that manuscript for 2 year now. 
       A. will be                 C. has been                           B. had been                     D. is
 23. I _______________there once a long time ago and _______________back since.
       A. went/have not been          B. go/am not             C. have gone/was            D. was going/had not been
24. In the last hundred years, traveling ___________much easier and more comfortable. 
       A. becomes              B. has become                 C. became                   D. will become 
25. It is raining now. It began raining two hours ago. So it ____ for two hours. 
       A. rains                    B. is raining                    C. has rained                   D. rained 
26. Mike is playing chess. How long ___________ he ____________?
       A. did/play                B. is/playing                  C. has/play                   D. has/been playing 
27. Today is Thursday and she ______ late twice this week. She ______ late yesterday and on Monday. 
        A. is/was                 B. has been/is                 C. has been/was            D. has been/had been
 28. He _______________ in the same house since 1975. 
        A. has lived            B. lived                            C. is living                   D. had lived
 29. We _______________ him since he ______________ married. 
        A. didn’t see/got             B. haven’t seen/got              C. don’t/get                D. hadn’t seen/got 
30. It _______________for two hours and the ground is too wet to play tennis. 
        A. is raining             B. had rained                  C. has rained                         D. was raining

Put the verbs in brackets in the present perfect or the simple past tense. 
1. It is very hot. Summer (come) _________. 
2. They (study) _________at this school for 7 years now.
3. They (begin) _________ to study at this school 7 years ago. 
4. Since when (you know) _________ her ? 
5. How long ago (he start) _________to learn French ? 
6. She (lose) _________ her handbag on the train yesterday morning.
7. My mother (be) _________ in hospital for a long time and she cannot go home yet. 
8. His dog (just run) _________ out of the garden. 
9. Mr Brown (travel) _________ by air several times in the past. 
10. He (travel) _________to Mexico by air last summer.

 Put the verbs in brackets in the present perfect or the simple past tense.
 1. We (never watch) _________that TV programme. 
2. We (watch) _________ a good programme on TV last night. 
3. He (read) _________ that novel many times before. 
4. He (read) _________that novel again during my last vacation. 
5. I (have) _________ a little trouble with my car last week. 
6. However, I (have) _________no trouble with my car since then. 
7. I (not see) _________ John for a long time. I (see) _________ him 3 weeks ago. 
8. The school bell (ring) _________. We must go now. 
9. I (meet) _________Mary last night. She (become) _________ a very big girl.
 10. He is very thirsty. He (not drink) _________ since this morning. 

Lập phương trình hóa học :

Fe(OH)₂ + O₂ + H₂O ---> Fe(OH)₃

C₄H₁₀ + O₂ ---> CO₂ + H₂O

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