BAI TAP CONDITIONAL SENTENCES BIẾN THỂ

CONDITIONAL SENTENCES – BIẾN THỂ VÀ CÁC HÌNH THỨC THAY THẾ IF
I. Rewrite the following sentences.
1. If you are not careful, you will cut yourself with that knife.
 Unless…………………………………………………………
2. If she doesn’t hurry, she will be late.
 Unless………………………………………………………….
3. If we had more rain, our crops would be better.
 Unless…………………………………………………………….
4. The crop would have been ruined if the flood had risen higher.
 Unless…………………………………………………………….
5. Keep silent or you will wake the baby up.
 If you…………………………………………………………….
6. If she had lent me money, she wouldn’t have lost it.
 As…………………………………………………………………..
7. If I were you, I’d accept the job.
 Were……………………………………………
8. If he hadn’t helped me, I couldn’t have overcome the difficulty.
 Had it not………………………………………………………………………………..
II. Give the correct form of the verbs in brackets.
1. Give the book to Jane if you (read) …………………………… it.
2. If you hadn't lost our flight tickets, we (be) …………………………… on our way to the
Caribbean now.
3. If you (have) …………………………… dinner right now, I'll come back later.
4. I’m homeless. If I (have) _________ money now, I (buy) ______________ a big house.
5. If we (set)……………………off earlier, we wouldn't be in this traffic jam now.
6. If she were sensible, she (not/ask)………………………………… that question, by which she
offended him so much.
7. If you (pour)…………..oil on water, it (float)…………….
8. We lost the match. If you (play) ______________ for us, we (win) __________.
III. Choose the best answer.
1. I didn’t have an umbrella with me, so I got wet.

A. If I had had an umbrella, I wouldn’t have got wet.
B. If I had had an umbrella, I wouldn’t have get wet
C. If I had had an umbrella, I wouldn’t get wet.
D. If I had had an umbrella, I would get wet
2. ……………. we find new sources, we will soon run out of energy.
A. If
B. When
C. Unless
D. Only
3. Do you think there should be less conflict in the world if all people………. the same language?
A. speak
B. spoke
C. will speak
D. had spoken
4. We would save thousands of lives if ................. the remedy for the flu.
A. we find out
B. we found
C. we will find
D. we had not found out
5. You can smoke here………. you leave a window open to let the smoke out.
A. whether
B. unless
C. as long as
D. until
1


6. George won’t lend you any money………. you promise to pay him back.
A. providing
B. unless

C. provided
D. as long as
7. If I were 5 years younger, I would ………….. that job.
A. apply to
B. apply for
C. apply into
D. apply in
8. If you inherited a million pounds, what………. with the money?
A. do you do
B. will you do
C. would you do
D. are you going to do
9. If you………. as I told you, you………. in such predicament now.
A. did/would not be
B. had done/had not been C. do/would not be D. had done/would not be
10. Get me a glass of lemonade if you………. to the kitchen.
A. go
B. going
C. went
D. will go
11. The education in Japan………. if the basic principles of education had not been taken into
consideration.
A. would go down
B. would have gone down
C. went down
D. had gone down
12. If there………., the rice fields could have been more productive.
A. had been enough water
C. would be enough water
B. were enough water

D. are enough water
13. The patient could not recover unless he………. an operation.
A. had undergone
B. would undergo
C. underwent
D. was undergoing
14. If it ……….convenient, let’s go out for a drink tonight.
A. be
B. is
C. was
D. were
15 She will accept the offer………. you persuade her.
A. unless
B. because
C. provided that
D. otherwise
16 If he were here, he would accompany you on the piano.
A. Supposing he were here
C. Because he were here
B. Were he here
D. Both A and B
17. If she had gone abroad, she would have let you know.
A. Had she go abroad
C. Because she had gone abroad
B. Had she gone abroad
D. While she had gone abroad
18……….she agreed, you would have done it.
A. If
B. Had
C. Should

D. Would
19. It would have been a much more serious accident………. fast at the time.
A. had she been driving B. was she driving
C. she had driven
D. she drove
20. I won’t accept unless .................
A. Tom to apologize
B. Tom apologizes
C. when to apologizes D. Tom is apologizing
21. ……….interested in that subject, I would try to learn more about it.
A. Were I
B. Should I
C. I was
D. If I am
22. ……then what I know today, I would have saved myself a lot of time and trouble over the years.
A. Had I known B. Did I know
C. If I know
D. If I would know
23. If I weren’t working for an accounting firm, I………. in a bank.
A. work
B. will work
C. have worked
D. would be working
24. Marge walked away from the discussion, otherwise she ………something she would regret later.
A. will say
B. said
C. might say
D. might have said
25. If it………. your help, I would have failed the exam.
2

A. hadn’t been for
B. had been for
C. hasn’t been for
D. has been for
26. Unless you help, we may not complete the project.
A. If you help, it isn’t possible that we cope with the project.
B. Without your help, we will complete the project.
C. If you don’t help, we won’t complete the project.
D. Provided you help, it is likely that we will overcome the project.
27. I didn’t understand what he was saying because I hadn’t read his book.
A. If I had read his book, I would understand what he was saying.
B. If I had read his book, I would have understood what he was saying.
C. If I had read his book, I would had understood what he was saying.
D. If I had read his book, I would be understanding what he was saying.
28. You should take the train instead of the bus.
A. If you were me, I’d take the train instead of the bus.
B. If I were you, I’d take the train instead of the bus.
C. If you were I, I’d take the train instead of the bus.
D. If I am you, I’d take the train instead of the bus.
29. If he attended the class regularly, he…………to sit for the exam.
A. would allow
B. allowed
C. would be allowed
D. would have alowed
30. ________ you if I ________ your phone number.
A. I'd phone / had not lost
B. I’d phone / had not lost
C. I'll phone / did not lose

D. I'd have phoned / had not lost
31. If the machine _______, press this button.
A. stop
B. stops
C. would stop
D. stoped
32. The lecturer didn’t know what he was talking about, but if Dr Mason _____ I would have
listened carefully.
A. lectured
B. was lecturing
C. would lecture
D. had been lecturing
33. I can’t understand what he sees in her! If anyone treated me like that, I _______extremely angry!
A. am
B. would be
C. will be
D. was
34. If you _____ up all the orange juice that was in that carton, you ought to go out and get some
more.
A. drank
B. drinking
C. drunk
D. drink
35. Rachel will be pleased _________ she passes her driving test.
A. should
B. will
C. if
D. unless
36. I _____ you sooner had someone told me you were in hospital.
A. visited

B. visit
C. would have visited
D. had visited
37. If you can give me one good reason for your acting like this, _____ this incident again.
A. I don’t mention
B. I will never mention
C. I never mention
D. will I never mention
38. You can use my car ___________ you drive carefully.
A. unless
B. as long as
C. as soon as
D. when
39. If everyone _____ an extra hour a day, it would greatly increase production.
A. work
B. works
C. working
D. worked
40. If energy _____ inexpensive and unlimited, many things in the world would be different.
A. is
B. were
C. will be
D. would be
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41. Don’t bother to ring me _________ it’s important.
A. unless
B. in case
C. if

D. as
42. If you help me with this exercise, I ________do the same for you one day.
A. will
B. would
C. was
D. am
43. According to the timetable, if the train _______ on time, we _______ arrive at 5.30.
A. leaves/ would
B. left/ would
C. leaves/ will
D. was leaving/ would
44. If I could speak Spanish, I_____next year studying in Mexico.
A. will spend
B. had spent
C. would spend
D. would have spent
45. The bus won’t stop__________you ring the bell.
A. if
B. as soon as
C. providing
D. unless
46. You’d better take a coat________it gets cold.
A. if
B. in case
C. as long as
D. while
47. If you_____to my advice in the first place, you wouldn’t be in this mess right now.
A. listen
B. will listen
C. listened

D. had listened
48. If it_____fine tomorrow, we will go to the coast.
A. will be
B. was
C. is
D. being
49. I don’t understand this point of grammar. I wish I______it better.
A. understood
B. would understand
C. had understood
D. understands
50.You_____ yourself ill if you don’t eat properly.
A. were to make
B. make
C. would make
D. will make
51. If the ball _____ the line, that would have been the end of the game.
A. had crossed
B. crossed
C. crosses
D. cross
52._____ more help, I could call my neighbour.
A. Should I need B. Needed
C. I have needed
D. I should need
53. Come on! _____ we hurry, we’ll miss the plane!
A. if
B. unless
C. in case
D. supposed

61. If I had known that you were in hospital, I _____ you.
A. would visit
B. would have visited
C. will visit
D. visited
55. I didn’t get home until after midnight last night. Otherwise, I _____ your call.
A. returned
B. had returned
C. would return
D. would have returned
56. If Jake _____ to go on the trip, would you have gone?
A. hadn’t agreed
B. doesn’t agree
C. didn’t agreed
D. wouldn’t agree
57. If I found Rob’s phone number now, I _____ him about the change in plans.
A. called
B. had called
C. could call
D. will call
58. If I see him, I _____ him a gift.
A. give
B. would give
C. will give
D. gave
59. If I had a typewriter, I _____ it myself.
A. typed
B. would have typed
C. would typed
D. am typing

60. If you don’t keep silent, you ________wake the baby up.
A. will

B. would

C. had

D. can

IV- Choose the best answer which has the same meaning with the given one.
1. If there isn’t enough rain, the hydropower station can not operate.
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A. When there isn’t enough rain, the hydropower station can operate.
B. Unless there is enough rain, the hydropower station can operate.
C. Unless there isn’t enough rain, the hydropower station can not operate.
D. Unless there is enough rain, the hydropower station can’t operate.
2. If we don’t save water, we will have to suffer from water shortage.
A. Unless we don’t save water, we will have to suffer from water shortage.
B. If we save water, we will have to suffer from water shortage
C. Unless we don’t save water, we won’t have to suffer from water shortage
D. If we save water, we won’t have to suffer from water shortage.
3. She is too weak; she can’t sit up and talk to you.
A. If she weren’t too weak, she could sit up and talk to you.
B. If she hadn’t been too weak, she could sit up and talk to you
C. If she isn’t too weak, she can sit up and talk to you
D. If she weren’t too weak, she can sit up and talk to you
4. I am too old now; otherwive, I will apply for that post.
A. If I would not be too old, I would apply for that job.

B. If I was not be too old, I will apply for that job.
C. If I were not too old, I would apply for that job.
D. If I am not too old, I will apply for that job.
5. It’s raining and they can’t go camping in the mountain.
A. If it was raining, they could go camping in the mountain.
B. If it isn’t raining, they could go camping in the mountain.
C. If it weren’t raining, they could go camping in the mountain.
D. If it is raining, they could go camping in the mountain.
V. One of the four underlined parts marked A, B, C, D in each sentence is not correct in
standard English. Identify them.
1. If Lucia had been here now, she would find out the truth about her uncle’s accident.
A
B
C
D
2. If a student takes a course on Computer Science, it will take him four years doing the course.
A
B
C
D
3. Unless it did not rain, Peter would pay us a visit.
A
B
C
D
4. If had I known you were in financial difficulty, I would have helped you.
A
B C
D
5. If I had knew the time when the match started, I would have told you.

A
B
C
D
6. If she had finished the work, she can go home.
A
B
C D
7. If I had spoken more confident at the interview, they would have offered me the job.
A
B
C
D
8. If we had had a map, we would not be lost yesterday.
5


A
B
C
D
9. Had I known Alice’s address, I would write to her.
A
B
C
D
10. If I had realized that the traffic lights were red, I would stop.
A
B
C

D
11. If had you sent the application form to that company, you would have been offered a job.
A
B
C
D
12. Unless you work harder, you will be sack because of your laziness.
A
B
C
D
13. Unless there had been the heavy storm, the climbers will not have died.
A
B
C
D
14. She has found that nobody can help her if she did not try her best to do it herself.
A
B
C
D
15. If you were here yesterday, you would have seen Jean.
A
B
C
D
16. We could had done more if we had had more time
A
B
C

D
17. He said that if he has more time, he would come to see us.
A
B
C
D
18. If you will study harder, you will surely pass the coming exams with good results.
A
B
C
D
19. If I am 10 centimeter taller, I would play basketball.
A
B
C
D
20. If I were you, I will go to the dentist’s and have the tooth checked.
A
B
C
D
21. If the weather weren’t too bad, we would to go swimming
A
B
C
D
22. Unless we leave a bowl of water under the sun, it will evaporate.
A
B
C

D
23. If he weren’t too old, he would apply to the job as a war reporter.
A
B
C
D

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KEY
CONDITIONAL SENTENCES
I. Rewrite the following sentences.
1. If you are not careful, you will cut yourself with that knife.
 Unless ..you are careful, you will cut yourself with that knife.
2. If she doesn’t hurry, she will be late.
 Unless…she hurries, she will be late…
3. If we had more rain, our crops would be better.
 Unless…we had more rain, our crop wouldn’t be better.
4. The crop would have been ruined if the flood had risen higher.
 Unless the flood had risen higher, the crop woudn’t have been ruined.
5. Keep silent or you will wake the baby up.
 If you..don’t keep silent, you will wake the baby up.
6. If she had lent me money, she wouldn’t have lost it.
 As long as she had lent the money, she wouldn’t have lost it.
7. If I were you, I’d accept the job.
 Were I you, I’d accept the job.
8. If he hadn’t helped me, I couldn’t have overcome the difficulty.
 Had it not been for his help, I couldn’t have overcome the difficulty.
II. Give the correct form of the verbs in brackets.

1. Give the book to Jane if you (read) …have read………………………… it.
2. If you hadn't lost our flight tickets, we (be) …would be………………………… on our way to the
Caribbean now.
3. If you (have) …are having………………………… dinner right now, I'll come back later.
4. I’m homeless. If I (have) __had_______ money now, I (buy) __would buy________a big house.
5. If we (set)…had set…………………off earlier, we wouldn't be in this traffic jam now.
6. If she were sensible, she (not/ask)…wouldn’t have asked…………that question, by which she
offended him so much.
7. If you (pour)…pour………..oil on water, it (float)…floats………….
8. We lost the match. If you (play) __had played___for us, we (win) would have won__________.
III. Choose the best answer.
1. I didn’t have an umbrella with me, so I got wet.
A. If I had had an umbrella, I wouldn’t have got wet.
B. If I had had an umbrella, I wouldn’t have get wet
C. If I had had an umbrella, I wouldn’t get wet.
D. If I had had an umbrella, I would get wet
2. ……………. we find new sources, we will soon run out of energy.
A. If
B. When
C. Unless
D. Only
3. Do you think there should be less conflict in the world if all people………. the same language?
A. speak
B. spoke
C. will speak
D. had spoken
4. We would save thousands of lives if ................. the remedy for the flu.
A. we find out
B. we found
C. we will find

D. we had not found out
7


5. You can smoke here………. you leave a window open to let the smoke out.
A. whether
B. unless
C. as long as
D. until
6. George won’t lend you any money………. you promise to pay him back.
A. providing
B. unless
C. provided
D. as long as
7. If I were 5 years younger, I would ………….. that job.
A. apply to
B. apply for
C. apply into
D. apply in
8. If you inherited a million pounds, what………. with the money?
A. do you do
B. will you do
C. would you do
D. are you going to do
9. If you………. as I told you, you………. in such predicament now.
A. did/would not be
B. had done/had not been C. do/would not be D. had done/would not be
10. Get me a glass of lemonade if you………. to the kitchen.
A. go
B. going

C. went
D. will go
11. The education in Japan………. if the basic principles of education had not been taken into
consideration.
A. would go down
B. would have gone down
C. went down
D. had gone down
12. If there………., the rice fields could have been more productive.
A. had been enough water
C. would be enough water
B. were enough water
D. are enough water
13. The patient could not recover unless he………. an operation.
A. had undergone
B. would undergo
C. underwent
D. was undergoing
14. If it ……….convenient, let’s go out for a drink tonight.
A. be
B. is
C. was
D. were
15 She will accept the offer………. you persuade her.
A. unless
B. because
C. provided that
D. otherwise
16 If he were here, he would accompany you on the piano.
A. Supposing he were here

C. Because he were here
B. Were he here
D. Both A and B
17. If she had gone abroad, she would have let you know.
A. Had she go abroad
C. Because she had gone abroad
B. Had she gone abroad
D. While she had gone abroad
18……….she agreed, you would have done it.
A. If
B. Had
C. Should
D. Would
19. It would have been a much more serious accident………. fast at the time.
A. had she been driving B. was she driving
C. she had driven
D. she drove
20. I won’t accept unless .................
A. Tom to apologize
B. Tom apologizes
C. when to apologizes D. Tom is apologizing
21. ……….interested in that subject, I would try to learn more about it.
A. Were I
B. Should I
C. I was
D. If I am
22. ……then what I know today, I would have saved myself a lot of time and trouble over the years.
A. Had I known B. Did I know
C. If I know
D. If I would know

23. If I weren’t working for an accounting firm, I………. in a bank.
A. work
B. will work
C. have worked
D. would be working
24. Marge walked away from the discussion, otherwise she ………something she would regret later.
8


A. will say
B. said
C. might say
D. might have said
25. If it………. your help, I would have failed the exam.
A. hadn’t been for
B. had been for
C. hasn’t been for
D. has been for
26. Unless you help, we may not complete the project.
A. If you help, it isn’t possible that we cope with the project.
B. Without your help, we will complete the project.
C. If you don’t help, we won’t complete the project.
D. Provided you help, it is likely that we will overcome the project.
27. I didn’t understand what he was saying because I hadn’t read his book.
A. If I had read his book, I would understand what he was saying.
B. If I had read his book, I would have understood what he was saying.
C. If I had read his book, I would had understood what he was saying.
D. If I had read his book, I would be understanding what he was saying.
28. You should take the train instead of the bus.
A. If you were me, I’d take the train instead of the bus.

B. If I were you, I’d take the train instead of the bus.
C. If you were I, I’d take the train instead of the bus.
D. If I am you, I’d take the train instead of the bus.
29. If he attended the class regularly, he…………to sit for the exam.
A. would allow
B. allowed
C. would be allowed
D. would have alowed
30. ________ you if I ________ your phone number.
A. I'd phone / had not lost
B. I’d phone / had not lost
C. I'll phone / did not lose
D. I'd have phoned / had not lost
31. If the machine _______, press this button.
A. stop
B. stops
C. would stop
D. stoped
32. The lecturer didn’t know what he was talking about, but if Dr Mason _____ I would have
listened carefully.
A. lectured
B. was lecturing
C. would lecture
D. had been lecturing
33. I can’t understand what he sees in her! If anyone treated me like that, I _______extremely angry!
A. am
B. would be
C. will be
D. was
34. If you _____ up all the orange juice that was in that carton, you ought to go out and get some

more.
A. drank
B. drinking
C. drunk
D. drink
35. Rachel will be pleased _________ she passes her driving test.
A. should
B. will
C. if
D. unless
36. I _____ you sooner had someone told me you were in hospital.
A. visited
B. visit
C. would have visited
D. had visited
37. If you can give me one good reason for your acting like this, _____ this incident again.
A. I don’t mention
B. I will never mention
C. I never mention
D. will I never mention
38. You can use my car ___________ you drive carefully.
A. unless
B. as long as
C. as soon as
D. when
39. If everyone _____ an extra hour a day, it would greatly increase production.
A. work
B. works
C. working
D. worked

9


40. If energy _____ inexpensive and unlimited, many things in the world would be different.
A. is
B. were
C. will be
D. would be
41. Don’t bother to ring me _________ it’s important.
A. unless
B. in case
C. if
D. as
42. If you help me with this exercise, I ________do the same for you one day.
A. will
B. would
C. was
D. am
43. According to the timetable, if the train _______ on time, we _______ arrive at 5.30.
A. leaves/ would
B. left/ would
C. leaves/ will
D. was leaving/ would
44. If I could speak Spanish, I_____next year studying in Mexico.
A. will spend
B. had spent
C. would spend
D. would have spent
45. The bus won’t stop__________you ring the bell.
A. if

B. as soon as
C. providing
D. unless
46. You’d better take a coat________it gets cold.
A. if
B. in case
C. as long as
D. while
47. If you_____to my advice in the first place, you wouldn’t be in this mess right now.
A. listen
B. will listen
C. listened
D. had listened
48. If it_____fine tomorrow, we will go to the coast.
A. will be
B. was
C. is
D. being
49. I don’t understand this point of grammar. I wish I______it better.
A. understood
B. would understand
C. had understood
D. understands
50.You_____ yourself ill if you don’t eat properly.
A. were to make
B. make
C. would make
D. will make
51. If the ball _____ the line, that would have been the end of the game.
A. had crossed

B. crossed
C. crosses
D. cross
52._____ more help, I could call my neighbour.
A. Should I need B. Needed
C. I have needed
D. I should need
53. Come on! _____ we hurry, we’ll miss the plane!
A. if
B. unless
C. in case
D. supposed
61. If I had known that you were in hospital, I _____ you.
A. would visit
B. would have visited
C. will visit
D. visited
55. I didn’t get home until after midnight last night. Otherwise, I _____ your call.
A. returned
B. had returned
C. would return
D. would have returned
56. If Jake _____ to go on the trip, would you have gone?
A. hadn’t agreed
B. doesn’t agree
C. didn’t agreed
D. wouldn’t agree
57. If I found Rob’s phone number now, I _____ him about the change in plans.
A. called
B. had called

C. could call
D. will call
58. If I see him, I _____ him a gift.
A. give
B. would give
C. will give
D. gave
59. If I had a typewriter, I _____ it myself.
A. typed
B. would have typed
C. would typed
D. am typing
60. If you don’t keep silent, you ________wake the baby up.
A. will
B. would
C. had
D. can
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IV- Choose the best answer which has the same meaning with the given one.
1. If there isn’t enough rain, the hydropower station can not operate.
A. When there isn’t enough rain, the hydropower station can operate.
B. Unless there is enough rain, the hydropower station can operate.
C. Unless there isn’t enough rain, the hydropower station can not operate.
D. Unless there is enough rain, the hydropower station can’t operate.
2. If we don’t save water, we will have to suffer from water shortage.
A. Unless we don’t save water, we will have to suffer from water shortage.
B. If we save water, we will have to suffer from water shortage
C. Unless we don’t save water, we won’t have to suffer from water shortage

D. If we save water, we won’t have to suffer from water shortage.
3. She is too weak; she can’t sit up and talk to you.
A. If she weren’t too weak, she could sit up and talk to you.
B. If she hadn’t been too weak, she could sit up and talk to you
C. If she isn’t too weak, she can sit up and talk to you
D. If she weren’t too weak, she can sit up and talk to you
4. I am too old now; otherwive, I will apply for that post.
A. If I would not be too old, I would apply for that job.
B. If I was not be too old, I will apply for that job.
C. If I were not too old, I would apply for that job.
D. If I am not too old, I will apply for that job.
5. It’s raining and they can’t go camping in the mountain.
A. If it was raining, they could go camping in the mountain.
B. If it isn’t raining, they could go camping in the mountain.
C. If it weren’t raining, they could go camping in the mountain.
D. If it is raining, they could go camping in the mountain.
V. One of the four underlined parts marked A, B, C, D in each sentence is not correct in
standard English. Identify them.
1. If Lucia had been here now, she would find out the truth about her uncle’s accident.
A
B
C
D
2. If a student takes a course on Computer Science, it will take him four years doing the course.
A
B
C
D
3. Unless it did not rain, Peter would pay us a visit.
A

B
C
D
4. If had I known you were in financial difficulty, I would have helped you.
A
B C
D
5. If I had knew the time when the match started, I would have told you.
A
B
C
D
6. If she had finished the work, she can go home.
A
B
C D
7. If I had spoken more confident at the interview, they would have offered me the job.
A
B
C
D
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8. If we had had a map, we would not be lost yesterday.
A
B
C
D
9. Had I known Alice’s address, I would write to her.

A
B
C
D
10. If I had realized that the traffic lights were red, I would stop.
A
B
C
D
11. If had you sent the application form to that company, you would have been offered a job.
A
B
C
D
12. Unless you work harder, you will be sack because of your laziness.
A
B
C
D
13. Unless there had been the heavy storm, the climbers will not have died.
A
B
C
D
14. She has found that nobody can help her if she did not try her best to do it herself.
A
B
C
D
15. If you were here yesterday, you would have seen Jean.

A
B
C
D
16. We could had done more if we had had more time
A
B
C
D
17. He said that if he has more time, he would come to see us.
A
B
C
D
18. If you will study harder, you will surely pass the coming exams with good results.
A
B
C
D
19. If I am 10 centimeter taller, I would play basketball.
A
B
C
D
20. If I were you, I will go to the dentist’s and have the tooth checked.
A
B
C
D
21. If the weather weren’t too bad, we would to go swimming

A
B
C
D
22. Unless we leave a bowl of water under the sun, it will evaporate.
A
B
C
D
23. If he weren’t too old, he would apply to the job as a war reporter.
A
B
C
D

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