Một số giải pháp nâng cao hiệu quả dạy học câu điều kiện trong chương trình tiếng anh lớp 11- trường ptdtnt tỉnh phần thứ nhấT: phần mở ĐẦU

10. Cách sử dụng if trong một số trường hợp khác

• 
  If... then: Nếu... thì
          If she can’t come to us, then we will have to go and see her.
  
• 
  If dùng trong dạng câu suy diễn logic (không phải câu điều kiện): Động từ ở các mệnh đề diễn biến bình thường theo thời gian của chính nó.
          If you want to learn a musical instrument, you have to practice.
          If you did not do much maths at school, you will find economics difficult to understand.
          If that was Marry, why didn’t she stop and say hello.
  
• 
  If... should = If... happen to... = If... should happen to... diễn đạt sự không chắc chắn.
  

• 
  If it + to be + not + for: Nếu không vì, nếu không nhờ vào.
  Thời hiện tại:
          If it wasn’t/weren’t for the children, that couple wouldn’t have any thing to talk about. 
  Thời quá khứ:
          If it hadn’t been for your help, I don’t know what to do.
  Not đôi khi được thêm vào những động từ sau if để bày tỏ sự nghi ngờ, không chắc chắn. (Có nên ... Hay không ...)
          I wonder if we shouldn’t ask the doctor to look at Mary.
  
• 
  It would... if + subject + would... (sẽ là... nếu – không được dùng trong văn viết)
          It would be better if they would tell every body in advance.
          How would we feel if this would happen to our family.
  
• 
  If...’d have...’d have: Dùng trong văn nói, không dùng trong văn viết, diễn đạt điều kiện không thể xảy ra ở quá khứ
          If I’d have known, I’d have told you.
          If she’d have recognized him it would have been funny.
  
• 
  If + preposition + noun/verb... (subject + be bị lược bỏ)
        If in doubt, ask for help. (= If you are in doubt, ...)
        If about to go on a long journey, try to have a good nights sleep. (= If you are about to go on... )
  
• 
  If dùng với một số từ như any/anything/ever/not để diễn đạt phủ định
  There is little if any good evidence for flying saucers.
  (There is little evidence, if there is any at all, for flying saucers)        I’m not angry. If anything, I feel a little surprised.
  Cách nói này còn diễn đạt ý kiến ướm thử: Nếu có...
  I’d say he was more like a father, if anything
  

Usually, if not always, we write “cannot” as one word

• 
  If + Adjective = although (cho dù là) 
  Nghĩa không mạnh bằng although
  

The profits, if little lower than last year’s, are still extremely wealthy

Eg. If he has money, he will buy a new car.

 Should he have money, he will buy a new car.

If Linda does not do her homework, she will be punished.

 Should Linda not do her homework, she will be punished.

Type 2:

If-clause = Were + S (+not) + to V…

Eg. If he knew the answer, he would tell you.

 Were he to know the answer, he would tell you.

If I were you, I would go abroad for studying.

 Were I you, I would go abroad for studying.

Type 3:

If-clause = Had + S (+ not) + P2…

Eg. If they had not gone to Huong pagoda by coach, they would not have got carsick.

 Had they not gone to Huong pagoda by coach, they would not have got carsick.

C. Câu điều kiện theo quan điểm mới

Theo quan điểm mới, Tiếng Anh có hai loại câu điều kiện chủ yếu. Đó là: Câu điều kiện biểu thị và câu điều kiện giả định.

Thì của động từ và trạng ngữ chỉ thời gian phải tương ưng nhau (tức là cùng nằm trên một bậc).

If my mother is at home now, …

If he is living in London at present, …

If John was in the theatre yesterday, …

If she has been learning English for seven years, …

b) Mệnh đề chính (main clause)

- Trợ động từ : WILL / CAN

- Động từ nguyên mẫu sau trợ động từ WILL:

+ present simple / future  Nguyên mẫu đơn (bare infinitive)

+ present progressive  Nguyễn mẫu tiếp diễn (be V-ing)

+ present perfect / past simple / past perfect  Nguyên mẫu hoàn thành (have PII)

+ past progressive / persent perfect progressive / past perfect progressive

 Nguyên mẫu hoàn thành tiếp diễn (have been V-ing)

Eg. If it does not rain tomorrow, we will go swimming.

If my mother is at home now, she will be cooking dinner.

If he is living in London at present, he will be working as an engineer.

If John was in the theatre yesterday, he will not go there again today.

If she has been learning English for seven years, she will have spoken this language fluently.

2. Câu điều kiện giả định

a) Mệnh đề điều kiện (If-clause)

Thì của động từ và trạng ngữ chỉ thời gian không tương ứng (tức là không cùng nằm trên một bậc).

Eg. If there were no air, …

If I were you, …

If he were staying at home now, …

If they had been living here for 6 years now, …

If we had not gone to Huong pagoda by coach yesterday, …

- Trợ động từ: WOULD / COULD

- Động từ nguyên mẫu sau trợ động từ WOULD:

+ present simple / future  Nguyên mẫu đơn (bare infinitive)

+ present progressive  Nguyễn mẫu tiếp diễn (be V-ing)

+ present perfect / past simple / past perfect  Nguyên mẫu hoàn thành (have PII)

+ past progressive / persent perfect progressive / past perfect progressive

 Nguyên mẫu hoàn thành tiếp diễn (have been V-ing)

Eg. If there were no air, no species would exist.

If I were you, I would make friend with her.

If he were staying at home now, he would be watching his favourite football matches.

If they had been living here for 6 years now, they would have had a lot of friends.

If we had not gone to Huong pagoda by coach yesterday, we would not have got carsick.

III. CÁC DẠNG BÀI TẬP VỀ CÂU ĐIỀU KIỆN

1. DẠNG BÀI TẬP TỰ LUẬN

1.1. Conditional sentences: Type 1

Example: If he runs, he will get there in time.

The cat will scratch you if you pull her tail.

1. David will leave for Ren tomorrow if the weather .......................... (be) fine.

2. What will you do if you ............................ (not / go) away for the weekend ?

3. The game .......................................... (start) if you put a coin in the slot.

4. If you ................................... (be) scared of spiders, don’t go into the garden.

5. We’ll have to go without John if he ( not arrive)…………….soon.

6. Please don’t disturb him if he ...................................... (be) busy.

7. If she ........... (accept) your card and roses, things will be very much hopeful.

8. If a holiday .................................... (fall) on a weekend, go to the beach.

9. If she (come)…………………………. late again, she’ll lose her job.

10. If he (wash)…………………………..my car, I’ll give him $20.

11. He’ll be late for the train if he (not start)………………………….. at once.

12. If I lend you $100, when you (repay)………………………… me?

13. Unless I have a quiet room I (not be able)……………..... to do any work.

14. If we leave the car here, it (not be)…………………….. in anybody’s way.

15. Someone (steal)…………………………. your car if you leave it unlocked.

16. Unless he (sell)………………….more, he won’t get much commission.

17. If you come late, they (not let)………………………. you in.

18. If you (not go)……………………….. away I’ll send for the police.

19. If he ..................................... (eat) all that, he will be ill.

20. What .................................. (happen) if my parachute does not open?

1.2. Conditional sentences: Type 2
Example: If I had a map, I would lend it to you.

If I were you , I’d plant some trees round the house.

Were they stronger, they could lift the table

Exercise 2: Put the verbs in brackets into the correct tenses.

1. If I knew his address, I (write)............. to him.

2. If the sun (be)................ shining now, we would go to the beach

3. If you (paint)…………….the walls white, the room would be much brighter.

4. If he knew that it was dangerous he (not come)……………………….

5. I (buy)…………………..shares in that company if I had some money.

6. If you drove more carefully, you (not have)………….. so many accidents.

7. If I (be)……….. you , I (not worry)………...............about going to university.

8. If I (have)…………………any money, I would give you some.

9. Mary doesn’t study hard. She (not pass)……… the examination unless she worked harder.

10. What you (buy)…………………….if your father gave you $200?

11. If I ( know)………..his phone number, I would call him.

12. We would need less money if we ( live)…………….in the country

13. How (you/ feel)……………. if you were in my position?

14. If he ............................ (get) up earlier, he’d get to work on time.

15. If I ....................... (be) you, I ...................... (tell) them the truth.

16. They would go to the beauty spot if they ........................... (have) time.

17. If we .............................. (have) a car, we would drive to work everyday.

18. Where you ........... (choose) if you could live anywhere in the world ?

19. You ................................ (catch) the train if you left earlier.

20. If I ...................................... (pass) the exam, he would be astonished.

21. I wouldn’t agree with him if he ............................ (tell) me about his plan.

22. If she ..........(elect) the Prime Minister, she would invest more on education.

23. If I ............................... (be) rich, I would live in a castle.

24. If you ............................. (not – work) so hard, you would find the time.

25. If he .................................. (work) harder, the result would be better.

- If the patient had got the treatment, he wouldn’t have đie.

- Had he studied hard, he would have passed the exam

Exercise 3: Put the verbs in brackets into the correct tenses.

1. If Mary (wear)…………a raincoat, she would not have got a cold.

2. There (not have)….....……an accident if the driver in front hadn’t stopped so suddenly.

3. If she had eaten something, she (not feel)………………………. hungry.

4. If I (have)………………a sound sleep last night I would have been well.

5. If it (not rain)…………yesterday we would have had lunch in t he garden.

6. If it had not been very expensive I (buy)…………………………..it.

7. If the teacher (speak)………………more slowly Peter would have understood the lessons.

8. If I ................. (have) my camera with me yesterday, I ...................... (take) a picture of Alex standing on his head.

9. The cowboy pulled his gun to shoot at the rattlesnake, but he was too late. If he ...................(be) quicker to pull the trigger, the snake ................... (not-bite) him on the foot.

10. If you ......................... (be) more careful, you wouldn't have cut yourself.

11. If Martin had set his alarm clock, he ................................ (not oversleep).

12. If you (speak)......................more slowly, he might have understood you.

13. If he had known the whole story, he (not be)..........................so angry.

14. If I (be)...............ready when he called, he would have taken me with him.

15. I didn't know you were in hospital. If I ................ (know), I ....................(go)

to visit you.

Exercise 4: Put the verbs in brackets into the correct tenses.

1. If I (be)…………… you, I (apply) …………for a job as soon as possible.

2. I could understand the French teacher if she (speak).................. more slowly.

3. If you (make) ………………………a run for it, you’ll catch the train.

4. If Laura (not eat) ………………so much, she wouldn’t have put on weight.

5. I (accept)................................... if they invite me to the party.

6.The earthquake would have caused less damage if the house (be) ………of stronger construction.

7. If there (be) ………………a good breeze on Sunday, we’ll go hang-gliding.

8.You can get there more quickly if you (take) …………the short cut across the playing field.

9. If he (be) ……………taller, he (be able) ………………to join the police.

10. If she (read)............................ in bad light, she’ll ruin her eyes.

11. If I were you, I (wear)....…some warm clothes today. It’s quite cold outside.

12. Don’t worry about getting home. If you (miss) ……......……the last bus, I’ll give you a lift in my car.

13. Jim would get better marks at school if he (do) …………more homework.

14. He (not leave) …………………his last job if the salary had been better.

15. What you (do) ………………if you saw someone drowning in the sea?

16. If I had any news, I (phone) ………………………you yesterday.

17. I don’t have much money, but if I (have) …......…, I (travel) …...……around the world.

18. If you (tell) ……………me he was ill, I (visit) ………him.

19. If you go in the rain without a raincoat, you (catch) ………………a cold.

20. If you had been at the party last Sunday, you (meet) …….........…some old friends.

21. I’d change this old motorcycle if I (have) …………...……enough money.

22. He would have died if the doctors (not operate) …………………on him.

23. If I had a car, I (give) ………………………you a ride.

24. If I meet Paul tomorrow, I (give) ………………………him your letter

25. If the weather (be)……nice next weekend, they (go) ………to the country.

26. If people (not eat) ……………so many sweets, their teeth wouldn’t fall out.

27. If we (take) ……………………your advice, we’d have saved a lot of time.

28. If you don’t hurry, we (be) ………………………late for the match.

29. If you didn’t smoke so many cigarettes, you (feel) ………………better.

30. She would be better-looking if she (not have) ………………such a big nose.

1.4. “Unless”

* “Unless” = If... not (nếu ...không, trừ phi)

• 
  Unless you study hard, you will fail the exam.
  

• 
  Unless she waters these trees, they will die.
  

• 
  Unless we had more rain, our crops wouldn’t grow faster.
  

1. I won’t go to school if I don’t feel better.

2. Tony will talk to you if you question him.

3. If you don’t put on your overcoat, you’ll be cold.

4. You will fail the exam if you don’t work hard.

5. You’ll get a cold if you don’t keep your feet dry.

6. If I don’t leave now, I’ll miss my flight.

7. If you aren’t going to the party, I won’t go.

8. I can’t send you a postcard if you don’t give me your address.

9. If I won a big prize in a lottery, I’d build a school for the poor.

10. I’ll call the police if you don’t leave me alone.

* That’s why + clause => Main clause

* Because + clause => If- clause

* Indicating clause of cause => If – clause

Clause of result => Main clause

Example: They don’t have enough time so they cannot do me a favour.

=> If they had time, they could do me a favour.

She has a sore throat. She doesn’t stop smoking.