Câu điều kiện – Conditional Sentences là loại câu dùng để nói về một điều kiện xảy ra và kết quả sẽ xảy ra nếu điều kiện đó được thỏa mãn. Nói đơn giản:
Nếu A xảy ra, thì B sẽ xảy ra
Ví dụ:
-
- If you heat water to 100°C, it boils.
→ Nếu bạn đun nước đến 100°C, nước sẽ sôi. (Đây là quy luật luôn đúng.)
-
- If I study hard, I will pass the exam.
→ Nếu tôi học chăm, tôi sẽ đậu. (Đây là dự đoán có khả năng xảy ra trong tương lai.)
-
- If I studied harder, I would pass the exam.
→ Nếu tôi học chăm hơn thì tôi đã đậu rồi. (Đây là giả định – không còn đúng với hiện tại.)
Chỉ cần nhìn ba ví dụ trên, có thể thấy:
Cùng là “nếu… thì…” nhưng mỗi câu cho thấy sự việc đó có chắc xảy ra, có thể xảy ra, hay chỉ là giả định. Đó chính là lý do vì sao câu điều kiện được chia thành nhiều loại khác nhau.
Tổng hợp về câu điều kiện
Câu điều kiện loại 0, loại 1, loại 2 và loại 3
Cấu trúc chung của một câu điều kiện luôn có
Câu điều kiện
| LOẠI |
CẤU TRÚC |
CÁCH DÙNG |
BẢN CHẤT |
VÍ DỤ |
| Zero Conditional |
If + Present Simple, Present Simple |
Diễn tả sự thật hiển nhiên, quy luật tự nhiên, điều luôn luôn đúng |
A xảy ra thì B luôn luôn đúng |
If you heat water to 100°C, it boils. → Nếu đun nước đến 100°C, nước sẽ sôi.If you don’t heat water to 100°C, it doesn’t boil.
If you heat water to 100°C, does it boil? |
| First Conditional |
If + Present Simple, will / may / might / could + V |
Diễn tả khả năng có thể xảy ra trong tương lai |
A có khả năng xảy ra, B là kết quả có thể xảy ra |
If I invest my money, it will grow. → Nếu tôi đầu tư, tiền sẽ sinh lời.
- If I don’t invest my money, it won’t grow.
- If you invest your money, will it grow?
|
| Second Conditional |
If + Past Simple, would / wouldn’t + V |
Diễn tả giả định không có thật ở hiện tại hoặc khó xảy ra trong tương lai |
A không đúng với thực tế hiện tại, B là kết quả tưởng tượng |
If I invested my money, it would grow. → Nếu tôi mà đầu tư (giả sử), tiền sẽ sinh lời.
- If I invested my money, it wouldn’t grow.
- If you invested your money, would it grow?
|
| Third Conditional |
If + had + V3, would / could / might + have + V3 |
Diễn tả một điều kiện không có thật trong quá khứ, và kết quả cũng đã không xảy ra.Thường dùng để tiếc nuối – trách – nói “giá như…” |
A đã không xảy ra trong quá khứ, B là kết quả đáng lẽ đã xảy ra nhưng thực tế không có. |
If I had studied harder, I would have passed the exam. → Nếu tôi đã học chăm hơn thì tôi đã đậu rồi.
- If I had not studied harder, I would not have passed the exam.
- If you had studied harder, would you have passed the exam?
|
Note: Khi If đứng đầu câu → có dấu phẩy, khi If đứng giữa → không có dấu phẩy
|
Ghi nhớ nhanh
- Diễn tả sự thật hiển nhiên, quy luật luôn đúng (loại 0)
- Dự đoán kết quả có thể xảy ra trong tương lai (loại 1)
- Nói về những giả định không có thật ở hiện tại (loại 2)
- Và diễn tả những điều kiện không có thật trong quá khứ, những việc đã không xảy ra và không thể thay đổi (loại 3)
- Ngoài ra còn có những cách diễn đạt mang tính phòng ngừa, ngoại lệ và điều kiện phủ định như unless, in case, as long as…
|
Bài tập thực hành câu điều kiện
Bài 1
| 1. If you ___ ice, it melts.
A. heat B. heated C. will heat D. have heated |
2. If she studies hard, she ___ pass the exam.
A. passed B. will C. would D. had |
3. If I were rich, I ___ a big house.
A. buy B. will buy C. would buy D. bought
|
| 4. If they ___ earlier, they wouldn’t be late now.
A. leave B. left C. had left D. will leave |
5. If you mix red and yellow, you ___ orange.
A. got B. get C. will get D. would get |
6. If he had known the truth, he ___ so angry.
A. wouldn’t be B. won’t be C. wouldn’t have been D. isn’t
|
| 7. If it ___ tomorrow, we will stay at home.
A. rains B. rained C. will rain D. had rained |
8. If I ___ you, I would accept that offer.
A. am B. was C. were D. had been |
9. If she had slept earlier, she ___ tired now.
A. wouldn’t feel B. wouldn’t have felt C. won’t feel D. didn’t feel
|
| 10. If you don’t water plants, they ___ die.
A. died B. would die C. will die D. had died |
11. If he ___ more carefully, he wouldn’t have made that mistake.
A. works B. worked C. had worked D. is working |
12. If people eat too much sugar, they ___ weight.
A. gained B. gain C. will gain D. would gain
|
| 13. If I had more time, I ___ learn French.
A. will B. would C. had D. can |
14. If you heat water to 100°C, it ___.
A. boiled B. will boil C. boils D. would boil |
15. If she ___ his advice, she would have avoided the problem.
A. follows B. followed C. had followed D. will follow
|
Bài 2: Tìm lỗi sai
| 1. If he would listen to the teacher, he could improve faster. |
2. If she had more time yesterday, she would finish the report. |
3. If people didn’t use plastic so much, the environment will be cleaner.
|
| 4. If I were you, I will not accept that risky offer. |
5. If they had studied harder, they wouldn’t feel so tired now. |
6. If it rains last night, the roads will be flooded now.
|
| 7. If he didn’t forget the ticket, he wouldn’t miss the flight yesterday. |
8. If you would pay attention, you wouldn’t keep making the same mistake. |
9. If she knows the rule, she would not break it again.
|
| 10. If I have saved more money, I would have bought that house last year. |
11. If he had listened to the advice, he will be more successful now. |
12. If people had prepared better, the damage will not be so serious.
|
| 13. If she were more confident, she would have applied for the job last week. |
14. If water had reached 100°C, it boils. |
15. If they don’t panic at that moment, they would have escaped safely.
|
Bài 3: Điền đáp án đúng
| 1. If people exercise regularly, they ____ healthier. |
2. If the bus arrives late, we ____ a taxi. |
3. If I had enough savings, I ____ my own café.
|
| 4. If she had followed the map, she ____ lost. |
5. If students copy homework, they ____ in trouble. |
6. If he had taken that job, he ____ abroad now.
|
| 7. If the temperature drops below zero, water ____ into ice. |
8. If you ____ more careful, this accident wouldn’t happen. |
9. If they had booked earlier, they ____ cheaper tickets.
|
| 10. If my phone battery dies, I ____ you later. |
11. If I were the team leader, I ____ the plan immediately. |
12. If children watch too much TV, they ____ less active.
|
| 13. If we had left on time, we ____ stuck in traffic now. |
14. If metal is heated long enough, it ____ red. |
15. If she didn’t ignore the warning, she ____ that mistake yesterday.
|
Đáp án
Bài 1: 1A – 2B – 3C – 4C – 5B – 6C – 7A – 8C – 9A – 10C – 11C – 12B – 13B – 14C – 15C
Bài 2:
| 1. would listen → listened |
2. had → had had |
3. will be → would be |
| 4. will not accept → would not accept |
5. wouldn’t feel → wouldn’t be feeling |
6. rains → had rained |
| 7. didn’t forget → hadn’t forgotten |
8. would pay → paid |
9. knows → knew |
| 10. have saved → had saved |
11. will be → would be |
12. will not be → would not be |
| 13. would have applied → would apply |
14. had reached → reaches |
15. don’t panic → didn’t panic |
Bài 3:
| 1. become |
2. will take |
3. would open |
| 4. wouldn’t have got |
5. will get |
6. would be |
| 7. turns |
8. were |
9. would have bought |
| 10. will call |
11. would change |
12. become |
| 13. wouldn’t be |
14. turns |
15. wouldn’t have made |
Các cấu trúc thay thế if trong câu điều kiện
Thay thế câu điều kiện
| Nhóm từ |
Từ / Cụm từ |
Bản chất ý nghĩa |
Khi nào dùng |
Ví dụ |
| 1. Điều kiện chắc chắn hơn “if” |
when |
Khi |
Người nói tin chắc sự việc sẽ xảy ra |
When I finish my work, I will call you. → Khi tôi làm xong việc, tôi sẽ gọi bạn.
|
|
as soon as |
Ngay khi |
Nhấn mạnh thời điểm xảy ra ngay lập tức |
I’ll call you as soon as I arrive. → Tôi sẽ gọi bạn ngay khi tôi đến nơi.
|
| 2. Điều kiện phủ định |
unless |
Trừ khi |
Dùng để diễn đạt if … not |
You won’t pass unless you study. → Bạn sẽ không đậu trừ khi bạn học.
|
| 3. Điều kiện ràng buộc – bắt buộc |
provided (that) |
Miễn là |
Nhấn mạnh điều kiện bắt buộc phải có (dùng nhiều trong văn viết) |
You can go provided that you finish your homework. → Bạn có thể đi miễn là bạn làm xong bài.
|
|
providing (that) |
Miễn là |
Nghĩa và cách dùng tương tự provided that |
We’ll help you providing that you tell us the truth.
|
|
as long as |
Miễn là |
Dùng phổ biến trong văn nói |
You can stay here as long as you keep quiet.
|
|
so long as |
Miễn là |
Trang trọng hơn as long as |
You can borrow my car so long as you drive carefully.
|
| 4. Điều kiện mang tính phòng ngừa |
in case |
Phòng khi, lỡ khi |
Làm trước để đề phòng rủi ro |
Take an umbrella in case it rains. → Mang ô theo phòng khi trời mưa.
|
Ghi nhớ nhanh:
- When / As soon as → dùng khi chắc chắn có xảy ra
- Unless → luôn mang nghĩa phủ định (if … not)
- Provided / Providing / As long as / So long as → điều kiện ràng buộc, bắt buộc
- In case → làm trước để phòng ngừa rủi ro. Không thường dùng “in case” ở đầu câu
Bài tập thực hành cấu trúc thay thế câu điều kiện
Bài 1
| 1. When the alarm ___, everyone leaves the building immediately.
A. rang B. rings C. will ring D. would ring |
2. Take your charger with you in case your phone ___ out of battery.
A. ran B. runs C. will run D. would run |
3. If she ___ more carefully yesterday, she wouldn’t be apologizing now.
A. drives B. drove C. had driven D. would drive
|
| 4. You won’t be allowed to enter ___ you show your ID card.
A. if B. provided C. unless D. as long |
5. I’ll send you the file as soon as I ___ the final approval.
A. receive B. received C. will receive D. would receive |
6. If this machine ___ overheated, it shuts itself down automatically.
A. was B. is C. will be D. would be
|
| 7. If they ___ the warning seriously, the accident would have been avoided.
A. take B. took C. had taken D. would take |
8. You may stay here so long as you ___ the house rules.
A. follow B. followed C. will follow D. would follow |
9. If I ___ the answer right now, I would tell you immediately.
A. know B. knew C. had known D. will know
|
| 10. We will cancel the trip if the storm ___ worse tonight.
A. get B. gets C. got D. would get |
11. If he had backed up the data, he ___ everything after the crash.
A. doesn’t lose B. wouldn’t lose C. wouldn’t have lost D. won’t lose |
12. As long as you ___ honest, nobody will blame you.
A. stay B. stayed C. will stay D. would stay
|
| 13. Provided that everyone ___ on time, the meeting can start early.
A. arrive B. arrived C. will arrive D. would arrive |
14. If she were more decisive, she ___ so many chances in the past.
A. won’t miss B. wouldn’t miss C. wouldn’t have missed D. doesn’t miss |
15. Bring warm clothes in case the temperature ___ suddenly at night.
A. dropped B. drops C. will drop D. would drop
|
Bài 2: Tìm lỗi sai
| 1. When the light will turn red, all vehicles must stop. |
2. If the server crashes tonight, the team fixes it tomorrow. |
3. If I knew her number now, I had called her already. |
| 4. Unless you will submit the form today, your request is rejected. |
5. As long as everyone follows the procedure, nothing would go wrong. |
6. If he had taken the safety course, he doesn’t injure his hand last week. |
| 7. In case the client will arrive early, prepare the documents in advance. |
8. If I am better at public speaking, I would lead the presentation. |
9. Provided that she signs the contract yesterday, we can start the project today. |
| 10. If our manager listens more carefully, the conflict would have been solved. |
11. As soon as the meeting will finish, the report is sent to all departments. |
12. If people recycle properly, the landfill would reduce significantly. |
| 13. So long as the system had worked normally, no manual check is needed. |
14. If the pilot notices the error earlier, the aircraft would land safely last night. |
15. If the staff don’t panic at that moment, the evacuation would be successful. |
Bài 3: Tự điền đáp án
| 1. If the engine overheats, the machine ____ automatically. |
2. When the manager arrives, the meeting ____ immediately. |
3. If I had known about the deadline, I ____ earlier.
|
| 4. Unless you ____ a backup, you may lose all the data. |
5. If she were more careful, she ____ that accident. |
6. As soon as the parcel arrives, they ____ you a message.
|
| 7. If people breathe polluted air for a long time, they ____ serious illnesses. |
8. Provided that he ____ the full payment today, we will activate the service. |
9. If they had followed the instructions, nothing ____ wrong.
|
| 10. If the temperature drops below zero, the lake ____ solid. |
11. If I were in your position, I ____ that offer without hesitation. |
12. In case the system fails, the backup generator ____ on automatically.
|
| 13. As long as workers ____ safety rules, accidents can be prevented. |
14. If she had prepared better, she ____ so nervous during the interview. |
15. Unless the passengers ____ calm, the evacuation will be delayed.
|
Đáp án
Bài 1
| 1. B |
2. B |
3. C |
| 4. C |
5. A |
6. B |
| 7. C |
8. A |
9. B |
| 10. B |
11. C |
12. A |
| 13. A |
14. C |
15. B |
Bài 2
| 1. will turn → turns |
2. fixes → will fix |
3. had called → would call |
| 4. will submit → submit |
5. would go → will go |
6. doesn’t injure → wouldn’t have injured
|
| 7. will arrive → arrives |
8. am → were |
9. yesterday → today |
| 10. would have been → would be |
11. will finish → finishes |
12. would reduce → will reduce |
| 13. had worked → works |
14. would land → would have landed |
15. would be → would have been |
Bài 3
| 1. shuts down |
2. starts |
3. would have finished |
| 4. make |
5. wouldn’t have had |
6. send |
| 7. develop |
8. makes |
9. would have gone |
| 10. freezes |
11. would accept |
12. switches |
| 13. follow |
14. wouldn’t have been |
15. remain |
