tổng hợp đầy đủ về lý thuyết câu điều kiện cùng với các ví dụ rõ ràng dễ hiểu và các dạng bài tập trắc nghiệm cả về cơ bản và nâng cao, giúp người học nắm bắt nhanh hơn, dễ dàng hơn. tài liệu có thể được sử dụng cho học tập và giảng dạy ở các cấp, đặc biệt là hữu ích cho việc ôn thi các trường đại học và cao đẳng
Conditional sentences 1. Type I: Real conditional sentences. If + S + V(present), S + will/ shall + V(infinitive) Eg: 1. If I am free, I will come to see you tomorrow 2. If you have finished your letter, I will post it Note: mệnh đề chính có thể dùng thì hiện tại đơn, thì hiện tại tiếp diễn, thì hiện tại hoàn thành để diễn tả một sự thật hiển nhiên hay quy luật của tự nhiên. Eg: If you mix blue and red, you get purple. 2. Type II: Unreal conditional sentences at present. If + S + V(past), S + would/ should + V(infinitive) Note: were được sử dụng trong tất cả các câu điều kiện loại II Eg: 1. If I were you, I would work harder 2. What would you do if you lived in Paris now? 3. Type III: Unreal conditional sentences in the past. If + S + had + PII(past perfect), S + would/ should/ could + have + PII Eg: 1. If I had gone there, I would have met him. 2. If she had had enough money, she would have bought that car. 4. Unless = If not Unless we start at once, we will be late = If we don't start at once, we will be late. Unless you study hard, you won't pass the exams = If you don't study hard, you won't pass the exams. Eg: 1. If I had taken my mother’s advice, I wouldn’t be ill today. 2. If she had revised the lessons well, she would do the test easily now. 5. Inversion in conditionals If I were the president, I would build more hospitals = Were I the president, I would build more hospitals. Were + S + , S + would + V(bare) If I had taken his advice, I would be rich now = Had I taken his advice, I would be rich now. Had + S + PII , I + would + V(bare) If He had learned hard, he would have passed the final exam = Had he learned hard, he would have passed the final exam. Had + S + PII , S + would have + PII 6. Mixed type of conditional sentences IF + S + PII + , S + WOULD/COULD + V(bare). Giả thiết ngược lại với điều gì đó đã xảy ra trong quá khứ và nhấn mạnh tới kết quả hiện tại đã bị ảnh hưởng của sự việc không xảy ra trong quá khứ đó. Eg: If I had taken his advice, I would be rich now. If I hadn't been in a hurry this morning, I wouldn't so hungry now. IF + S+PII, S + would/ could have + PII Sự việc trái với thực tế hiện có, dẫn đến kết quả về một sự việc không thực ở quá khứ. Eg: My brother is not a policeman. So, he could not help the boys when they asked. >If my brother were a policeman, he could have helped the boys when they asked. C hoose 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 got 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. If I had millions of dollars, I would ………… all over the world. A. be travelled B. travelling C. travel D. to travel 4. If you work hard, you will eventually A. succeed B. successful C. successfully D. success 5. “Will you come to the party tomorrow?” – “I will if I no visitors “ A. have B. will have C. had D. am having 6. If it ………… too cold, we could go on a picnic. A. isn’t B. wouldn’t be C. weren’t D. wouldn’t be 7. If you were not sick, ………… with us? A. will you come B. would you come C. do you come D. are you coming 8. If I were you, I would persuade him ………… the new treatment. A. to try B. trying C. tries D. try 9. If gravity, the pull of the earth, is zero, everything A. will float B. would be floating C. floated D. would float 10. If an object is let off in the cabin of a spaceship, it ……………. A. floated B. is floating C. will float D. would float 11. 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 12. If you will study harder, you will surely pass the coming exams with good results. A B C D 13. If I am 10 centimeter taller, I would play basketball. A B C D 14. If I were you, I will go to the dentist’s and have the tooth checked. A B C D 15. If the weather weren’t too bad, we would to go swimming A B C D 16. If the doctors could find in the remedy, a lot of people would be saved. A B C D 17. If he bought that house now, she ran out of money. A B C D 18. If he weren’t too old, he would apply to the job as a war reporter. A B C D 19. What you would do if you could speak French well? A B C D 20. If I had money, I will buy a car. A B C D 21. If we don’t stop to destroy forests, soon there will be no forest left on the earth. A B C D 22. If we will reduce the speed of population growth, there will be less presure on the earth. A B C D 23. If we do nothing for preserve their habitat, some species will become extinct. A B C D 24. Unless we leave a bowl of water under the sun, it will evaporate. A B C D 25. If we continue to use fuels at the current rate, we would soon have to face a fuel crisis. A B C D 26. Men will continue to live on foods unless other types of protein are not found. A B C D 27.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. 28.If we can t prevent it in advance, the hurrican will destroy the coastal towns.’ A. Unless we can prevent it in advance, the hurrican will destroy the coastal towns. B. Unless we can prevent it in advance, the hurrican won’t destroy the coastal towns. C. Unless we can’t prevent it in advance, the hurrican won’t destroy the coastal towns. D. When we can’t prevent it in advance, the hurrican won’t destroy the coastal towns. 29.If we don t save water, we will have to suffer fromn water shortage.’ A. Unless we don’t save water, we will have to suffer from water shortage. B. If we save water, we won’t 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 will have to suffer from water shortage. 30.She is too weak; she can t sit up and talk to you’ . A. If she wasn’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 wasn’t too weak, she can sit up and talk to you 31.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 oo old, I would apply for that job. D. If I am not too old, I will apply for that job. 32.I don t have enough money with me now; otherwise I will buy that coat.’ A. If I didn’t have enough money with me now, I would buy that coat. B. If I had enough money with me now, I would buy that coat. C. If I had enough money with me now, I wouldn’t buy that coat. D. If I didn’t have enough money with me now, I wouldn’t buy that coat. 33.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 wasn’t raining, they could go camping in the mountain. D. If it is raining, they could go camping in the mountain. . + S + V(past), S + would/ should + V(infinitive) Note: were được sử dụng trong tất cả các câu điều kiện loại II Eg: 1. If I were you, I would work harder 2. What would you do if you lived in. sentences IF + S + PII + , S + WOULD/COULD + V(bare). Giả thiết ngược lại với điều gì đó đã xảy ra trong quá khứ và nhấn mạnh tới kết quả hiện tại đã bị ảnh hưởng của sự việc không xảy ra trong. now. IF + S+PII, S + would/ could have + PII Sự việc trái với thực tế hiện có, dẫn đến kết quả về một sự việc không thực ở quá khứ. Eg: My brother is not a policeman. So, he could not help the