CHUYÊN đề 14 ĐỘNG Từ KHUYẾT THIẾU - 123doc

Can cũng diễn tả một điều có thể xảy đến possibility.. Can not được dùng để diễn tả một điều không thể xảy ra.. Could được dùng để diển tả một sự ngờ vực hay một lời phản kháng nhẹ nhàng

CHUYÊN ĐỀ 14: CÁC ĐỘNG TỪ KHUYẾT THIẾU

(MODAL VERBS)

Đặc tính chung của động từ khuyết thiếu (modal verbs)

1 Động từ khuyết thiếu được theo sau bởi một động từ nguyên thể bare infinitive.

S + Modal Verbs + V(bare-infinitive)

Ví dụ: They can speak French and English.

2 Không biến đổi dạng thứ trong các ngôi.

Ví dụ: He can use our phone (He use your phone).

I CAN - COULD

A Can

Can chỉ có 2 thì: Hiện tại và Quá khứ đơn Những hình thức khác ta dùng động từ tương đương “be able to” Can cũng có thể đuợc dùng như một trợ động từ để hình thành một số cách nói riêng.

1 Can và could có nghĩa là “có thể”, diễn tả một khả năng (ability).

Ví dụ: Can you swim?

She could ride a bicycle when she was five years old

2 Can cũng diễn tả một điều có thể xảy đến (possibility) Trong câu hỏi và câu cảm thán can có nghĩa là

“Is it possible ?”

Ví dụ: Can it be true?

It surely can’t be four o’clock already!

3 Can not được dùng để diễn tả một điều không thể xảy ra.

Ví dụ: He can’t go to the zoo because of the rain.

B Could

1 Could là thì quá khứ đơn của can.

Ví dụ: She could swim when she was five.

2 Could còn được dùng trong câu điều kiện.

Ví dụ: If you tried, you could do that work.

3 Trong cách nói thân mật, Could được xem như nhiều tính chất lịch sự hơn CAN.

Ví dụ: Can you change a 20-dollar note for me, please?

Could you tell me the right time, please?

4 Could được dùng để diển tả một sự ngờ vực hay một lời phản kháng nhẹ nhàng.

Ví dụ: His story could be true, but I hardly think it is.

I could do the job today, but I’d rather put it off until tomorrow

II MAY - MIGHT

1 May và dạng quá khứ Might diễn tả sự xin phép, cho phép (permission).

Ví dụ: May I take this book? - Yes, you may

She asked if she might go to the party

2 May/ Might dùng diễn tả một khả năng có thể xảy ra hay không thể xảy ra.

Ví dụ: It may rain.

He admitted that the news might be true

III MUST

1 Must có nghĩa là “phải” diễn tả một mệnh lệnh hay một sự bắt buộc.

Ví dụ: You must drive on the left in London.

2 Must dùng trong câu suy luận logic.

Ví dụ: Are you going home at midnight? You must be mad!

You have worked hard all day; You must be tired

3 Must Not (Mustn’t) diễn tả một lệnh cấm.

Ví dụ: You mustn’t walk on the grass.

 Chú ý:

- Have to dùng thay cho must trong những hình thức mà must không dùng được.

Ví dụ: We will have to hurry if we are going to catch the twelve o’clock train.

- Have to không the thay thế must trong câu suy luận logic.

Ví dụ: He must be mad.

- Must và have to đều có thể dùng để diễn tả sự cưỡng bách, bắt buộc (compulsion) Tuy nhiên must thể

hiện sự bắt buộc đến từ người nói trong khi have to diễn tả sự bắt buộc đến từ phía bên ngoài (ví dụ các

quy định pháp luật)

Ví dụ: You must do what I tell you (Bạn phải làm điều mà tớ bảo bạn.)

Passengers must cross the line by the bridge (Lệnh của Cục Đường Sắt)

Passengers have to cross the line by the bridge (Vì không còn đường nào khác)

IV SHALL - SHOULD

A Shall

Được dùng trong những trường hợp sau:

- Dùng trong cấu trúc thì Tương lai (Simple Future) ở ngôi thứ nhất

Ví dụ: I shall do what I like.

- Diễn tả một lời hứa (promise), một sự quả quyết (determination) hay một mối đe dọa (threat)

Ví dụ: If you work hard, you shall have a holiday on Saturday (promise)

He shall suffer for this; he shall pay you what he owes you (threat)

These people want to buy my house, but they shan’t have it (determination)

B Should

Được dùng để khuyên ai đó nên làm điều gì

Ví dụ: You should do what the teacher tells you.

- Dùng thay cho ought to, had better.

V Will-Would

1 Will

- Được dùng ở thì Tương lai (simple future), diễn tả một kế hoạch (plan), sự mong muốn (willingness), một lời hứa (promise) hay một sự quả quyết (determination)

- OK! I will pay you at the rate you ask (willingness)

- I won’t forget little Margaret’s birthday I will send her a present (promise)

2 Would

- Dùng để hình thành thì Tương lai trong quá khứ (future in the past) hay các thì trong câu điều kiện

Ví dụ: He said he would send it to me, but he didn’t.

If she were here, she would help US

He would have been very happy if he had known about it

- Diễn tả một thói quen trong quá khứ Với nghĩa này, Would có thể dùng thay cho used to.

Ví dụ: Every day he would get up at six o’clock and light the fire.

VI Ought to

Ought to có nghĩa là “nên”, gần giống với should Trong hầu hết các trường hợp ought to có thể được

thay thế bằng should

Ví dụ: They ought to (should) pay the money.

He ought to (should) be ashamed of himself

VII Used to

- Used to diễn tả một thói quen thường xuyên xảy trong quá khứ.

Ví dụ: He used to go fishing when he was small.

Chú ý dạng phủ định và nghi vấn:

S + used + to V Khẳng định

Nghi vấn Did + S + V?

Phân biệt USED TO và một số hình thức khác

- Used to + infinitive: hành động liên tục trong quá khứ

- (Be) Used to + V-ing: quen với một việc gì

- (Get) Used to + V-ing: làm quen với một việc gì

Ví dụ: He used to work six days a week (Now he doesn’t)

It took my brother two weeks to get used to working at night Now he’s used to it

BÀI TẬP VẬN DỤNG

Exercise 1: Complete each sentence with can/ could/ be able to (not).

1 you swim when you were 10?

2 We get to the meeting on time yesterday because the train was delayed by one hour

3 He arrive at the party on time, even after missing the train, so he was very pleased

4 He’s amazing, he speak 5 languages including Chinese

5 I drive a car until I was 34, then I moved to the countryside so I had to learn

6 I looked everywhere for my glasses but I find them anywhere

7 I searched for your house for ages, luckily I find it in the end

8 She’s 7 years old but she read yet - her parents are getting her extra lessons

9 I read the book three times but I understand it

10 James speak Japanese when he lived in Japan, but he’s forgotten most of it now

Exercise 2: Complete each sentence with can/ could/ be able to (not).

1 I understand the chapter we had to read for homework It was so difficult

2 I lift this box - it’s too heavy! Would you help me?

3 Lucy make it to our meeting after all She’s stuck in traffic at the moment

4 John play tennis really well He’s champion of his club

5 Unfortunately, I really sing at all! No-one in my family is musical either

6 When the car broke down I was really pleased because I solve the problem

7 Julian play excellent golf when he was only ten

8 My grandmother use a computer until last month Since then, she’s been taking lessons at the library

9 I open this window I think it’s stuck!

10 Julia play the piano She’s never studied it

Exercise 3: Complete each sentence with might/ must/ should (not).

1 Nancy said you didn't need to buy her anything for her birthday, but I really think you at least get her some flowers or a nice bottle of wine

2 Debbie said she was really busy this week, but I think she show up at the party if she doesn't have to work overtime on Friday

3 Nina said she would come over right after work, so she be here by 6:00

4 Oh my God, he's unconscious Don't move him – he have internal injuries

5 Dan: Where's the remote control? I want to change the channel

Fiona: I don't know It be under the couch

6 Experts agree that to master a foreign language, you practice the language regularly

7 New research suggests that exercise can reduce the chance of heart disease as well as cancer That's why I told my father that he start walking once a day

8 We invite Sally and her husband to come to the picnic on Saturday We haven't seen them in weeks

9 We had better call Tony to see if he's at home before we go over to his house He be there and we don't want to drive all the way over there for nothing

10 At first, my boss didn’t want to hire Sam But I told my boss that he take another look at his resume and reconsider him for the position

11 You worry so much If you don't get this job, just apply for another one

12 I would love to go on the cruise with Michelle But such a luxurious trip cost a fortune I

doubt I could afford something like that.

13 As some people be allergic to chemicals in artificial plant foods, gardeners use

an organic brand to avoid skin irritations

14 I know Eve wants to go to the ballet with us, but we call her before we get her ticket as she might be busy that night

15 It be a bad idea to take some snacks along while we're hiking Last time, we got so hungry

we had to come back early without finishing the hike

Exercise 4: Complete each sentence with must/ or have to (not).

1 You be kidding! That can't be true

2 I be at the meeting by 10:00 I will probably take a taxi if I want to be on time

3 You forget to pay the rent tomorrow The landlord is very strict about paying on time

4 You be so rude! Why don't you try saying "please" once in a while

5 If you are over 18 in California, you take a driver training course to get a driver's license You can have a friend or a family member teach you instead

6 You be rich to be a success Some of the most successful people I know haven't got a penny

to their name

7 Ed: My car broke down in Death Valley last week I have it towed more than a hundred miles to the nearest mechanic

8 While hiking in Alaska, you keep an eye out for bears If you see one, you approach it They are beautiful animals; however, they are wild and unpredictable in nature

9 I go to work tomorrow because it is Memorial Day The best thing about a day off from

work is that I get up at 6:00

10 Yesterday, I cram all day for my French final I didn't get to sleep until after midnight

11 Emily: Oh no! I completely forgot we were supposed to pick Jenny up at the airport

Barbara: She still be sitting there waiting for us

12 Ingrid received a scholarship which will cover 100% of the tuition She worry at all about the increasing cost of education

13 When I was a child my grandmother was continually correcting our manners She always used to say,

"One eat with one's mouth open."

14 I've redone this math problem at least twenty times, but my answer is wrong according to the answer key The answer in the book wrong!

15 You submit the application if it has not been completely filled out If the form is not

accurate and complete, you will be rejected and you will reapply at a later date

Exercise 5: Complete each sentence with could/might (not).

1 Unfortunately, James and Michelle had already made plans, so they

exhibition

2 You do the job if you didn't speak Arabic fluently

come with us to the

3 In order to win the pie eating contest, he would have to eat sixteen pies in ten minutes He possibly eat that many pies - he would explode!

4 Susan hear the speaker because the crowd was cheering so loudly

5 It be a bad idea to take some snacks along while we're hiking

6 They have had several major snow storms in the mountains during the last month The road to

Smithsville be passable

7 Jerry be angry at me I've never done anything to upset him

8 The lamp be broken Maybe the light bulb just burned out

9 When you were a child, you swim from here to the little island in the middle of the river, couldn't you?

10 She possibly be the winner of the talent show! The other acts were much better than hers

11 Ted's flight from Amsterdam took more than 11 hours He must be exhausted after such a long flight

He prefer to stay in tonight and get some rest

12 I heard that band is really popular, and tickets sell out quickly You get tickets if you wait

too long.

13 Please make sure to water my plants while I am gone If they don't get enough water, they die

14 It be a bad idea to get a car alarm for your new sports car New cars tend to attract thieves

15 That possibly be Mr Jones He's lost so much weight that he looks like a completely

different person

Exercise 6: Complete each sentence with can/ could/have to/must/might/ should (not).

1 That concert has been sold out for weeks You get tickets even if you knew the band personally It's impossible!

2 If you want to get a better feeling for how the city is laid out, you

explore the waterfront

walk downtown and

3 Hiking the trail to the peak be dangerous if you are not well prepared for dramatic weather changes You research the route a little more before you attempt the ascent

4 When you have a small child in the house, you leave small objects lying around Such objects might be swallowed, causing serious injury or even death

5 Dave: you hold your breath for more than a minute?

Nathan: No, I can't

6 Frank and Sarah get tickets to the concert The concert was sold out a little over an hour after tickets went on sale

7 Danny: I borrow your lighter for a minute?

Stephen: Sure, no problem Actually, you keep it if you want to I've given up smoking

8 I speak Arabic fluently when I was a child and we lived in Egypt

9 Leo: Where is the spatula? It be in this drawer but it's not here

Nancy: I just did a load of dishes last night and they're still in the dish washer It be in there That's the only other place it be

10 You take your umbrella along with you today The weatherman on the news said there's a storm north of here and it might rain later on this afternoon

ANSWER KEY

Exercise 1: Complete each sentence with can/ could/ be able to (not).

Exercise 2: Complete each sentence with can/ could/ be able to (not).

Exercise 3: Complete each sentence with might/ must/ should (not).

Exercise 4: Complete each sentence with must/ or have to (not).

4 don't have to 9 don't have to; don't have to 14 must be

Exercise 5: Complete each sentence with could/might (not).

6 might not 7 couldn't 8 might not 9 could 10 couldn't

Exercise 6: Complete each sentence with can/ could/ have to/ must/ might/ should (not).