Could

should

ought to

had better

will

could

would

will

Can

would

must

may

1 Could

2 should

3 ought to

4 had better

5 will

6 could

7 would

8 will

9 Can

10 would

11 must

12 may

1 may

2 couldn't

3 should

4 must

5 can

6 might

7 Will

8 ought to

Động từ đứng sau đọng từ khuyết thiếu là đọng từ nguyên thể .

VD: I can swim.

Cách dùng của các động từ khuyết thiếu( can, could, have to, must, will, should, ought to, had better, might, will be able to ) là dùng những động từ nguyên thể đứng sau động từ khuyết thiếu đó.

Example: I could ride a bike when I was six.

- Động từ khiếm khuyến “can” thường dùng để diễn tả về một khả năng

Ex: I can speak 4 languages: english, spanish, russia and french
(Tôi có thể nói bốn thứ tiếng: tiếng Anh, tiếng Tây Ban Nha, tiếng Nga và tiếng Pháp)

- Thể phủ định “can’t” diễn tả một điều không thể, không có khả năng thực hiện

Ex: I can’t love him even he gave me all his money
(Tôi không thể yêu anh ta dù cho anh ta đã cho tôi tất cả tiền bạc)

- Thể nghi vấn dùng để xin phép hoặc một sự yêu cầu

Ex: Can I use your cell phone?
(Tôi có thể dùng điện thoại của bạn không?)

Can you help me, sir?
(Thưa ngài, ngài có thể giúp tôi không?)

- “Could” có thể được dùng để xin phép

Ex: Could I borrow your motobike for 2 hours?
(Tôi có thể mượn xe máy của bạn trong 2 tiếng đồng hồ không?)

- Đưa ra một yêu cầu

Ex: Could you turn the light off?
(Bạn có thể tắt đèn không?)

- Đưa ra một lời đề nghị

Ex: We could go out for dinner tonight
(Chúng ta có thể ra ngoài ăn tối nay)

- Một khả năng trong tương lai

Ex: I think we could have another house in future
(Tôi nghĩ chúng ta sẽ có một căn nhà khác trong tương lai)

- Một khả năng trong quá khứ

Ex: I broke up with Daina so I could have a new love
(Tôi đã chia tay với Daina nên tôi có thể có một tình yêu mới)

- “May” dùng để đưa ra sự xin phép

Ex: May I have another glass of orange juice?
(Có thể lấy cho tôi một ly nước cam khác không?)

- Diễn tả khả năng trong tương lai

Ex: China may become a major economic power
(Trung Quốc có thể sẽ trở thành một cường quốc về kinh tế)

- Đưa ra một yêu cầu giúp đỡ

Ex: May I help you something, madam?
(Tôi có thể giúp gì cho bà không, thưa phu nhân?)

Choose the best option for each sentences:

1. Laura, you and the kids just have dinner without waiting for me. I......work very hard today.

A. Can B. May C. Should D. Would

2. I........ be delighted to show you round the factory.

A. Ought to B. Would C. Might D. Can

3. Leave early so that you....... miss the bus.

A. Didn’t B. Won’t C. Shouldn’t D. Mustn’t

4. Jenny’s engagement ring is enormous!!’ It....... have cost a fotune

A. Must B. Might. C. Will. D. Should

5. You....... to write them today

A. Should. B. Must. C. Had D. Ought

6. I hope i......... fin it

A. Will. B. Shall. C. Could. D. Must

7. Unless he runs he...... catch the train

A. Will. B. Mustn’t. C. Wouldn’t. D. Won’t

8. .......... you be in Rome tonight.

A. Will. B. May. C. Might. D. Maybe

9. We....... have time to help you tomorrow.

A. May. B. Must. C. Will D. Could

10. “........ you hand me that pair of scissors, please?”

A. May. B. Will. C. Shall. D. Should

1. Laura, you and the kids just have dinner without waiting for me. I......work very hard today.

A. Can B. May C. Should D. Would

2. I........ be delighted to show you round the factory.

A. Ought to B. Would C. Might D. Can

3. Leave early so that you....... miss the bus.

A. Didn’t B. Won’t C. Shouldn’t D. Mustn’t

4. Jenny’s engagement ring is enormous!!’ It....... have cost a fotune

A. Must B. Might. C. Will. D. Should

5. You....... to write them today

A. Should. B. Must. C. Had D. Ought

6. I hope i......... fin it

A. Will. B. Shall. C. Could. D. Must

7. Unless he runs he...... catch the train

A. Will. B. Mustn’t. C. Wouldn’t. D. Won’t

8. .......... you be in Rome tonight.

A. Will. B. May. C. Might. D. Maybe

9. We....... have time to help you tomorrow.

A. May. B. Must. C. Will D. Could

10. “........ you hand me that pair of scissors, please?”

A. May. B. Will. C. Shall. D. Should

modal verbs ( defective verbs ) ( can , could , may , might , shall , should , will , would , must , ought to )

Barbara will eat the cake

The cake will be eaten by Barbara.

You ought to send the package by registered mail

The package ought to be sent by registered mail

They cannot hold the metting in that room

The meeting cannot be held in that room

Will many people attend the lecture ?

Will the lecture be attended ?

You must do it right now

It must be done right now.

NObody can measure the depth of this river

The depth of this river can not be measured .

People can't take reference books home

Reference books home can't be taken

How much will they pay you ?

How much will you be paid?

They shouldn't build the resort on such a beautiful beach

The resort shouldn't be built on such a beautiful beach

We ought to clarify the problem of environment pollutiion

The problem of environment pollution ought to be clarified

They may organize a new group last week

A new group may be organized last week

1. The question can be answered.

2. The box would be carried.

3. The window should be opened.

4. Cards might be played.

5. The car ought to be washed.

6. The form must be filled in.

7. Could the dog be fed?

8. Could the door be locked by Jenny?

1. I can be answered the question.

2.she could be carried the box

3.you should be opened the window 

4 we might be played cards

5. you ought to be washed the car

6. he must be filled in the form.

7 . could you be fed the dog ? 

8 could jenny locked the door?

1: when my farther was young , he ….... work in the garden for long hours

A: can B: could C: will D: should

2: He ........ have comminitted the crime because he was with me that day

A: must B: shouldn't C: won't D: couldn't

5: Since we have to there by 8.30 , we ........ take a taxi

A: Had better B: May C: ought. D : are able to

6: It ...... rain this evening . Why don't you take an umbrelly ?

A: could be B: must C: might. D : will

7: ....... you help me with the homework ?

A: may. B: shall. C: should. D: will

8: she hasn't eaten anything since yesterday. She..... be really hungry

A: might. B: will. C: must. D : can

9: I put my keys on the table, but now it's gone. Someone.....have taken it

A: may. B: had to. C: should. D: would rather

10: Daisy is reading her English test because she has a test tomorrow. She .....be studying

A: will. B: should. C: must. D: can

11: We ....... put the fish in the fridge before it spoils

A: had to B: may. C: can. D: had better

1: when my farther was young , he ….... work in the garden for long hours

A: can B: could C: will D: should

2: He ........ have comminitted the crime because he was with me that day

A: must B: shouldn't C: won't D: couldn't

5: Since we have to there by 8.30 , we ........ take a taxi

A: Had better B: May C: ought. D : are able to

6: It ...... rain this evening . Why don't you take an umbrelly ?

A: could be B: must C: might. D : will

7: ....... you help me with the homework ?

A: may. B: shall. C: should. D: will

8: she hasn't eaten anything since yesterday. She..... be really hungry

A: might. B: will. C: must. D : can

9: I put my keys on the table, but now it's gone. Someone.....have taken it

A: may. B: had to. C: should. D: would rather

10: Daisy is reading her English test because she has a test tomorrow. She .....be studying

A: will. B: should. C: must. D: can

11: We ....... put the fish in the fridge before it spoils

A: had to B: may. C: can. D: had better