Modal Verbs – Động từ khuyết thiếu (+ V1)
1)

CÁCH DÙNG 1: “MODAL VERBS + V1”

CAN

COULD

CÔNG DỤNG / nghĩa
Năng lực
Xin/cho phép
Yêu cầu, đề nghị
Năng lực quá khứ
Gợi ý
Điều kiện 2,3
Yêu cầu, đề nghị
Xin/cho phép

WILL

WON’T

WOULD

Sẽ chắc chắn xảy ra, hứa,
đoán “I think,…”
Thói quen hiện tại :
“thường, sẽ”
Yêu cầu
Đề nghị

Đều kiện 1
“Không chịu, sẽ không”
(hiện tại)

Qúa khứ của WILL
Mời : “Would you like…
Thói quen quá khứ :
“thường, sẽ”
Yêu cầu

Đều kiện 2, 3
WOULDN’T “Không chịu” (quá khứ)

MAY

Xin, cho phép
Đều kiện 1

VÍ DỤ
I can ride a bike.
Can I go out?
Can you help me?
I could ride a bike when I
was 6.
You could ask him for
help
Could you say it again?
Could I speak to John,
please?
I’ll be old one day.

When she is angry, she
will go out for fresh air.
Will you wait for me?
I will help you.

QUÁ KHỨ (NẾU CÓ)
COULD

WOULD
WOULD

However hard you try to
WOULDN’T
convince her, she won’t
change her mind. (Cho dù
bạn cố gắng thuyết phục
cô ấy như thế nào, cô ấy
cũng không chịu đổi ý
định đâu)
He said he would come.
Would you like to come?
When
Would you tell me the
time, please?
When she was angry, she
would go out for fresh
air.(khi giận, cô ấy
thường đi ra ngoài hít
thở)
May I go out?


MIGHT


MIGHT
SHALL

SHOULD

MUST =
HAVE TO

Quá khứ của MAY
“Sẽ” = will
“có thể” : đề nghị
Đều kiện 1
“nên”: khuyên = BE
SUPPOSED TO, OUGHT
TO, HAD BETTER
Qúa khứ của “shall”
Mời: “Should you like…
“phải”: = BE SUPPOSED
TO, OUGHT TO, HAVE
GOT TO
“cần phải” = NEED

MUSTN’T

“không được phép”


NEED
NEEDN’T =
DON’T
HAVE TO
DARE /
DAREN’T

“cần”

OUGHT TO
(OUGHTN’
T TO)

“nên, phải” = SHOULD,
BE SUPPOSED TO,
MUST

2)

“dám / không dám”

He said it might rain.
SHOULD
Shall we go shopping
now?
You should mind your
words. (Bạn nên cẩn thận
lời nói)
He said it should rain.
Should you like to come?

I must go home now.

HAD TO

I need go home now.
(Chú ý: “need to” là
động từ thường)
You mustn’t use mobile
phone in class.
I need go home now.
You needn’t hurry. (Bạn
không cần vội)
I daren’t ask him.
Dare you? Bạn dám
không?
I ought to see him.

CÁCH DÙNG 2:

SUY
ĐOÁN

KHUYÊN

Ở HIỆN TẠI

Ở QUÁ KHỨ

PHỦ ĐỊNH


Must V1 : chắc là
Can’t V1: không thể nào

Must have V3,ed: chắc là đã
Can’t have V3/ed: không thể
nào đã
May have V3,ed: có thể đã
Could have V3,ed: có thể đã
Would have V3,ed: có thể đã
Might have V3/ed: có thể đã
Should have V3/ed: đã nên, lẽ
ra đã nên
Ought to have V3/ed: đã nên,
lẽ ra đã nên

Can’t…

May V1 : có thể
Could V1 : có thể
Would V1: có thể
Might V1: có thể
Should V1 : nên
Ought to V1: nên

May not…
Couldn’t…
Wouldn’t…
Mightn’t…
Shouldn’t…
Oughtn’t to…



Be supposed to V1: nên
SỰ CẦN
THIẾT

Need V1: cần
Needn’t V1: không cần

Be supposed to have V3/ed:
Be not supposed
đã nên, lẽ ra đã nên
to…
Need have V3/ed: đã cần phải Needn’t…
Needn’t have V3/ed: đã không
cần phải

EXERCISE 1: Complete the following sentences with “could / should / shouldn’t / must +
have + V3” or “should / must + V1”.
1. Susan failed her Economics 201 last term. She............very upset (be).
2. This computer isn’t fast enough. I know. I………….a better one, but I didn’t have enough
money when I bought this last month. (buy)
3. Why did you stay at a hotel when you went to New York? You………with Barbara. (stay)
4. Jack fell off a ladder yesterday but he’s all right. He’s lucky he……… himself badly.(hurt)
5. The situation was bad but it………worse. (be)
6. You have been traveling all day. You ………tired (be)
7. I’ve lost one of my gloves. I …………it somewhere (drop)
8. Carol …………very bored in her job. She does the same thing everyday.(get)
9. Jane walked past me without speaking. She…………me (see)
10. The phone rang but I didn’t hear it . I ……………asleep (be)

11. I haven’t seen the people next door for ages . They…………….(go away)
12. That restaurant……………very good. It’s always full [full]of people. ( be)
13. That restaurant …………very good. It’s always empty. (be)
14. It rained every day during their holiday, so they………………a very nice time (have)
15. Congratulations on passing your exam. You………………very pleased .(be)
16. Bill and Sue go away on holiday very often, so they………………short of money ( be)
17. Ted isn’t at work today. He………………ill. ( be)
18. Ted wasn’t at work last week. He………………ill( be )
19. Carol knows a lot about films. She………………to the cinema a lot. (go)
20. It was a great party last night. You ………………Why didn’t you? (come)
21. I’m feeling sick. I………………so much chocolate . ( eat)
22. You look tired . You ………………to bed now (go)
23. You went to bed very late last night . You………………to bed earlier.(go)
24. I wonder why they are so late. They………………here an hour ago.( be)
25. I’m sorry I didn’t take your advice . I ………………what you said (do)
26. She was too far away, so she ……………… you.( not /see)
27. Don passed the exam without studying for it. The exam ………………very difficult ( be)
28. She knew everything about our plans. She………………to our conversation (listen)
29. The lights were red but the car didn’t stop. The driver………………the red light ( see)
30. The trip was canceled last week. Paul ……….anyway because he was ill (go)


EXERCISE 2:Choose the best answer:
1. You ......out last night. I called several times but nobody answered the phone.
a. must be
b. must have been c. could have been d. should have been
2. Micheal’s score on the test is the highest in the class; .........last night.
a. he must have studied hard
b. he should have studied hard
c. he must study hard

d. he must had to study hard
3. Look! The yard is wet. It ......last night.
a. must rain
b. couldn’t have rained
c. must have rained
d. should have rained
4. We ....you more help, but we were too busy.
a. might have given
b. might give
c. should give
d. could give
5. You ....your pass at the entrance unless you are asked to do so.
a. mustn’t show
b. needn’t show
c. haven’t to show d. B &C
6. My supervisor is angry with me. I didn’t do all the work I .....last week.
a. must have done
b. may have done c. should have done
d. need to have done
7. You .... smoke in here. It’s against the rules.
a. shouldn’t
b. mightn’t
c. mustn’t
d. needn’t
8. He ....to the doctor after the accident, but he continued to play instead.
a. must have gone
b. should have gone c. couldn’t go
d. didn’t have to go
9. The kitchen ....dirty because she has just cleaned it.
a. should be

b. can’t be
c. mustn’t be
d. may be
10. Tim looks so frightened and upset. He.... something terrible.
a. must experience
b. can have experienced
c.should have experienced
d. must have experienced