Making deductions الاستنتاج

في حالة التعبير عن الاستنتاج في المضارع نستخدم:

must  I am certain that he isn’t clever.

can’t He can’t be clever.

may + inf.

might  Perhaps she speaks German well.

could She may speak German well.

أحيانا يمكن أن تعبر الجملة عن الاستمرار وفي هذه الحالة نستخدم:

Must  What is Ali doing in his room?

Can't I'm not sure. He may be studying.

May + be + V+ing  What is Linda doing?

Might She must be working on her computer.

could

في حالة الاستنتاج في الماضي:

Must have + PP. تعبر عن استنتاج مثبت مؤكد في الماضي

Can’t have + PP. تعبر عن استنتاج منفي مؤكد في الماضي

May have + PP. تعبر عن شيء ممكن أو محتمل في الماضي

Might have + PP. تعبر عن شيء أقل احتمالا في الحدوث

could have + PP. = may have / might have + PP

واذا كانت الجملة تعبر عن الاستمرار نستخدم:

Must have  What was he doing in the early morning?

Can’t have He must have been doing the exercises.

May have + been + V+ing  The light was on in his room after midnight.

Might have He must have been studying.

could have

The streets are wet. It must have rained last night.

 He was here a minute ago. He can’t have gone too far.

 He doesn’t get the same train any more. He may have changed his job.

(=Perhaps he changed his job)

 I haven’t seen Melissa for ages. She might have moved. (=Perhaps she moved.)

 يمكن استخدام could بدلا من may / might :

 و يمكن أن تعبر could have + PP أيضا عن شيء كان من الممكن حدوثه ولكنه لم يحدث:

Could have + PP.

 He hasn’t visited us for a long time. He could have been busy. (= He may/might have been busy)

 He was able to do the job but he didn’t.

He could have done the job.

Question tags

السؤال المضاف للجملة معناه دائمـا "أليس كذلك؟"

السؤال يكون عكس الجملة في الإثبات و النفي.

 في السؤال المضاف للجملة نستخدم دائما ضمير فاعل.

 Atef is a student, isn’t he?  Sara hasn’t got any money, has she?

لاحظ الحالات الشاذة الآتية:

 تعبر let’s عن الاقتراح أما let us فتعبر عن طلب الإذن:

 Let’s go, shall we?

 Let us stay here, will you?

 في حالة وجـود am نستخدم في السؤال aren’t وفي حالة وجود am not نستخدم am:

 I am a teacher, aren’t I?

 I am not a lawyer, am I?

 لاحظ أن الكلمات everyone / someone / everybody / somebody / no one/ nobody يأتي بدلا منها في السؤال they:

 Everyone has done the homework, haven’t they?

 Everybody’s at the match, aren’t they?

 Nobody saw the robbers, did they?

 الكلمات something / everything / nothing يأتي بدلا منها في السؤال it:

 Something has happened, hasn’t it?

الكلمات الآتية تعبر عن النفي ولذلك يكون السؤال مثبت:

seldom / never / scarcely / neither / little / few / hardly / rarely / no longer

 He no longer comes early, does he?

 There’s hardly any food, is there?

في حالة الأمر المنفي نستخدم في السؤال will you :

 Don’t open the door, will you?

 في حالة الأمر المثبت نستخدم عادة won’t you و يمكن أيضا استخدام will you:

 Close that door, won’t you?

 لاحظ أن الجمل التي تبدأ بـ I think / I believe يكون السؤال المذيل على الجزء الثاني ولكن الجملة التي تبدأ بـ I don't think/I don't believe تعتبر منفية:

 I think Hala will win the race, won’t she?

I don't think they are lazy, are they?

 لاحظ أننـا دائما نستخدم الاختصار في السؤال: don’t/didn’t/doesn’t/isn’t

في حالة وجود have كفعل أساسي يمكن استخدام have أو do في السؤال:

 He has a car, doesn’t he? (OR : hasn’t he?)

لاحظ استخدام Question tag مع التعبيرات الآتية :

You'd better leave, hadn't you?

You'd rather go, wouldn't you?

لاحظ استخدام there في السؤال المضاف للجملة :

 There isn't any milk in the fridge, is there?

لاحظ استخدام it بدلا من this / that في السؤال :

 This is not right, is it?

في حالة وجود IF يكون السؤال علي الجزء الثاني من الجملة(جواب الشرط) :

 If she doesn't have a map, she'll get lost, won't she?

في حالة وجود أكثر من فعل مساعد في الجملة نستخدم أول فعل مساعد في السؤال :

 They should have come earlier, shouldn't they?

Grammar Exercises:

1- Choose the correct answer from a, b, c or d

1. He (must have – can't have – didn't have – can have) missed his train. He's usually late.

2. His watch (must have – might have – could have – can't have) cost a lot of money. It's made of plastic.

3. It (can't have – will have – must have – didn't have) been very windy during the night. There are branches all over the ground.

4. Tunnelling under the Nile (must have – may have – can't have – might have) been easy. I'm sure it was difficult.

5. My father (didn't have – won't have – shall have – must have) walked to work this morning. His car is still in the garage.

6. He can't walk. He (must – mustn't – shouldn't – won't) be ill.

7. He spends so much money. He (can't – shouldn't – must – won't) be rich.

8. You (can't have – must have – should have – will have) finished that book already. You bought it only yesterday and it is very long.

9. A: I don't know where my school bag is, Mum? B: It's not here. You (mustn't – can't – might – won't) have left it on the train.

10. A: Look, Hesham's keys are on the table. B: He (must have - can't have – might have – may have) seen them when he left this morning.

11. A: I rang you this morning, but you didn't answer. B: Sorry, I (can't – might not – may not – must) have been asleep.

12. A: He's only been in the laboratory for ten minutes. B: Surely he (must – can't – might – may) have finished the experiment already.

13. A: Ali fell off his bike this morning. Do you know if he's OK? B: His mother says he (might – will – can – didn't) have broken his arm.

14. He (can't have – mustn't have – must have – should have) been injured. There was blood on his face.

15. The streets are wet. It (must rain – can't rain – must have rained – should have rained) last night.

16. Mona is never late, (is she – isn't she – won't she – will she)?

17. I'm not rich enough to buy that car, (aren't I – don't I – can I – am I)?

18. Not everyone enjoys sport, (do they – don't they – didn't he – does he)?

19. Let's go out tonight, (will you – won't you – should we – shall we)?

20. She'd rather not sign the cheque, (did she – hadn't she – wouldn't she – would she)?

Find the mistake in each of the following sentences then write it correctly:

1. He can't be rich. He owns two cars and a large house.

2. He must be ill. He eats like a horse.

3. You've been travelling all day. You can't be tired.

4. They haven't lived here for very long. They must know many people.

5. Ali hasn't contacted me. He mustn't have got my message.

6. She must be here. I know for certain that she's away on holiday.

7. She must have arrived. I'm not sure.

8. She must have arrived yet. It's much too early.

9. I can't find the theatre tickets. They must fall out of my pocket.

10. I could go out but I didn't feel like it, so I stayed at home.

11. A: What do you think of my theory? B: I'm not sure. You must be right.

12. A: Do you know where Hala is? B: No, I suppose she should have gone shopping.

13. He doesn't speak Arabic. He must be Egyptian.

14. He never does any work, but he's always at the top of his class. He can't be very clever.

15. Tom might have written this letter because it is in French and he doesn't know French.

16. He mustn't have seen the accident. He was ill in bed when it happened.

17. She's been arrested for murder, isn't she?

18. She rarely reads the papers, hasn't she?

19. Neither of them attended the meeting, didn't they?

20. They dug the well a week ago, don't they?

Language to deduce information

Why do you think (they built the Suez Canal)?	I think they must have (built it to make travelling by sea easier).
How do you think (they built the Suez Canal)?	Well, they might have used (thousands of workers).
What problems and difficulties do you think there were in (building..)?	I'm sure it can't have been easy. Surely, it must have cost a lot of money.