1. Harry Potter and the Goblet of Fire ________ by J K Rowling.

     A. written                      B. was written               C. wrote                        D. were written

2. Only half of the exercises ________ so far, but the rest ________ by Saturday.

A. are being done / will be finished

B. were done / are going to be finished

C. have been done / will have been finished

D. have done / will be finished

3. Because of the general pardon most of the prisoners ________ by the end of this year.

     A. will have been released                                  B. are being released

     C. are released                                                    D. have been released

4. The students ________ to stand up while the national anthem ________ and the flag ________.

     A. are taught / is sung / was raised

     B. taught / sang / is being raised

     C. are taught / is being sung / is being raised

     D. were taught / sang / raise

5. The medicine ________ at a high place where the children can't reach.

     A. must be kept             B. must keep                 C. must be keeping       D. must not keep

6. Nothing ________ because it was very foggy and raining heavily.

     A. is seen                      B. could be seen            C. haven't been seen     D. wasn't seen

7. When Jack arrived to the workshop his car ________.

     A. still being repaired                                          B. was still repaired

     C. was repairing                                                 D. was still being repaired

8. English ________ at state schools as a compulsory lesson for 20 years until last year.

     A. is being taught                                                B. was being taught

     C. had been taught                                              D. has been taught

9. The flood victims ________ with food and clean water by the volunteers.

     A. provided                   B. were provided          C. were providing         D. provide

10. Persons under the age of 20 ________ to take driving license but now they ________ to.

     A. are not allowed / were                                    B. were not allowed / are allowed

     C. are going / were going                                   D. were going / are not going

41. By the end of next March, I _______ English for five years.

     A. had been studied                                            B. had been studying

     C. will have been studying                                 D. will have studied

42. Linda took great photos of butterflies while she _______ in the forest.

     A. was hiking                B. is hiking                    C. hiked                        D. had hiked

43. When I _______ for my sister in front of the supermarket, a strange man came to talk with me.

     A. was waiting              B. waited                       C. had waited                D. were waiting

44. When I came to visit her last night, she _______ a bath.

     A. is having                   B. was having               C. has had                     D. had had

45. John _______ in the same house since he left school.

     A. lived                         B. had lived                   C. was living                 D. has lived

46. He will take the dog out for a walk as soon as he _______ dinner.

     A. finish                        B. has finished              C. will finish                 D. finished

47. The phone _______ suddenly while Joanna was doing the housework.

     A. rang                          B. was ringing               C. had rung                   D. is ringing

48. A fire-fighter was injuried severely while he _______ to put out a fire.

     A. would help               B. helped                       C. has helped                D. was helping

49. By the time I came here all the better jobs _______ taken.

     A. have been                 B. were                         C. are                            D. had been

50. While Peter _______ the rose bush in the back yard, the phone rang.

     A. had been watering    B. watering                   C. watered                     D. was watering

31. By the time he arrives here tomorrow, they _______ for London.

     A. would have left        B. will have left             C. will left                     D. are leaving

32. When I _______ to the airport, I realized that I _______ my passport at home.

     A. got/had left               B. got/left                      C. had got/had left         D. got/was left

33. Call me as soon as you _______ your test results.

     A. get                            B. will get                     C. will have got             D. got

34. I _______ along the street when I suddenly heard footsteps behind me.

     A. was walking             B. am walking               C. walk                         D. walked

35. The boy fell while he _______ down the stairs.

     A. run                            B. running                     C. was running              D. runs

36. I will come and see you before I _______ for America.

     A. leave                         B. will leave                  C. have left                    D. left

37. She hurt herself while she _______ hide-and-seek with her friends.

     A. is playing                  B. had played                C. played                       D. was playing

38. Only after the bus _______ for a few miles did Jane realize she was on the wrong route.

     A. was running             B. had run                     C. has run                      D. runs

39. While I _______ at the bus stop, three buses went by in the opposite direction.

     A. was waiting              B. waited                       C. had waited                D. were waiting

40. By the end of last March, I _______ English for five years.

     A. had been studied                                            B. had been studying

     C. will have been studying                                 D. will have studied

21. I was angry when you saw me because I _______ with my sister.

     A. have been arguing                                          B. had been arguing

     C. argued                                                            D. would argue

22. By the time I finish the final term exams, I _______ my first two years' study at university.

     A. have completed        B. will be completed     C. will complete            D. will have completed

23. I wanted to say goodbye to Jerry, but he _______ when I arrived.

     A. was already left                                              B. already left

     C. had already been leaving                               D. had already left

24. I saw a terrible accident while I _______ on the beach.

     A. am walking              B. walked                      C. was walking             D. had walked

25. When we see Mr. Minh tomorrow, I _______ him of that.

     A. will remind               B. remind                      C. have reminded          D. reminded

26. As soon as I _______ a good look at the designs, I _______ them back to you.

     A. have had/ sent                                                B. have had/ will send

     C. have/ send                                                      D. will have/ send

27. His English has improved a lot since he _______ an English course by Mr. John.

     A. was taking                B. takes                         C. took                          D. will take

28. We’ll be able to leave for the airport as soon as the taxi _______.

     A. arrived                      B. will arrive                 C. arrive                        D. arrives

29. Tom often watches TV after his parents _______ to bed.

     A. had gone                  B. have gone                 C. go                             D. went

30. When I last saw him, he _______ in London.

     A. is living                    B. has been living         C. was living                 D. lived

11. When the first child was born, they _______ for three years.

     A. have been married                                          B. had been married

     C. will been married                                           D. will have been married

12. We _______ in silence when he suddenly _______ me to help him.

     A. walked - was asking                                      B. were walking - asked

     C. were walking - was asking                            D. walked - asked

13. By the time the software _______ on sale next month, the company _______ $2 million on developing it.

     A. went - had spent                                             B. will go - has spent

     C. has gone - will spend                                     D. goes - will have spent

14. When Carol _______ last night, I _______ my favorite show on television.

     A. called / was watching                                     B. had called / watched

     C. called / have watched                                     D. was calling / watched

15. I'll call you as soon as I _______ in Paris.

     A. will arrive                 B. am arriving               C. arrive                        D. will have arrived

16. Many of the people who attended Major Gordon’s funeral _______ him for many years.

     A. didn't see                  B. wouldn't see             C. haven’t seen             D. hadn’t seen

17. Jane _______ her homework when her friend asked her to do his as well.

     A. did                            B. would do                  C. was doing                 D. had done

18. Mr. Pike _______ English at our school for 20 years before he retired last year.

     A. was teaching            B. had been teaching     C. is teaching                D. has been teaching

19. When I return to my hometown, everything _______ a lot.

     A. changes                    B. will be changing       C. will have changed    D. will change

20. My parents have left for English since I _______ at primary school.

     A. have been                 B. was                           C. had been                   D. am

1. Only after she _______ from a severe illness did she realize the importance of good health.

     A. would recover          B. has recovered           C. had recovered           D. was recovering

2. The children _______ to bed before their parents came home from work.

     A. were all going          B. had all gone              C. had all been going D. have all gone

3. Paul noticed a job advertisement while he _______ along the street.

     A. was walking             B. would walk C. walked                                   D. had walked

4. I haven’t met him again since we _______ school ten years ago.

     A. have left                   B. leave                         C. left                            D. had left

5. Mr Pike _______ for this company for more than thirty years, and he intends to stay here until he _______.

     A. worked/retires                                                B. works/is retiring

     C. has worked/retires                                          D. is working/will retire

6. When he _______ us to go in, we _______ outside the exam room for over half an hour.

     A. let - are standing                                             B. let - have stood

     C. let - had been standing                                   D. let - have been standing

7. When I _______ her, I _______ her your regards.

     A. met/was sending       B. meet/will send          C. met/had sent             D. meet/sent

8. When we enter the room, our boss _______ for us here.

     A. will wait                   B. will be waiting          C. was waiting              D. will be waited

9. When I got home I found that water _______ down the kitchen walls.

     A. ran                            B. was running              C. has run                      D. had been running

10. Mike _______ his favorite program on TV when the lights went out.

     A. was watching           B. is watching               C. watched                    D. watches

a) \(\sin2x=\dfrac{-1}{2}\)

b) \(\sin\dfrac{x}{2}=-1\)

c) \(\sin3x=\dfrac{1}{3}\)

d) \(\sin4x=-\sin x\)

Tìm \(\alpha\) biết:

a) \(\sin\alpha=0\)

b) \(\sin\alpha=1\)

c) \(\sin\alpha=-1\)

d) \(\cos\alpha=0\)

e) \(\cos\alpha=1\)

f) \(\cos\alpha=-1\)