Phân biệt cách sử dụng CAN, COULD và (BE) ABLE TO

[Butchi]

PHÂN BIỆT CÁCH SỬ DỤNG CAN, COULD VÀ (BE) ABLE TO
​

A. Chúng ta sử dụng can để nói rằng một điều gì đó là có thể hoặc ai đó có khả năng làm việc gì đó.

Chúng ta sử dụng can + infinitive (can do / can see etc.):

- We can see the lake from our bedroom window.
- Can you speak any foreign languages?
- I can come and see you tomorrow if you like.

Phủ định là can't (= cannot):

- I'm afraid I can't come to the party on Friday.

B. (Be) able to … có thể được dùng thay cho can, nhưng can vẫn thông dụng hơn:

- Are you able to speak any foreign languages?

Nhưng can chỉ có hai dạng thức, can (present) và could (past). Đôi khi cần phải sử dụng (be) able to …. So sánh:

- I can't sleep.
nhưng
- I haven't been able to sleep recently. (can không sử dụng được với thì hiện tại hoàn thành)

- Tom can come tomorrow.
but
- Tom might be able to come tomorrow. (can không có dạng nguyên mẫu)

View attachment 10767

C. Could và was able to …

Đôi khi could là quá khứ của can. Chúng ta sử dụng could đặc biệt với:
see hear smell taste feel remember understand

- When we went into the house, we could smell burning.
- She spoke in a very low voice, but I could understand what she said.

Chúng ta cũng sử dụng could để nói rằng ai đó có khả năng hoặc được phép làm gì đó:

- My grandfather could speak five languages.
- We were completely free. We could do what we wanted. (= we were allowed to do …)

Chúng ta sử dụng could để nói về những năng lực chung chung. Nhưng nếu chúng ta đang nói về những gì đã xảy ra trong một tình huống cụ thể, chúng ta sử dụng was/were able to … hoặc managed to … (không dùng could):

- The fire spread through the building quickly but everybody was able to escape.
hoặc … everybody managed to escape. (không nói could escape)
They didn't want to come with us at first but we managed to persuade them.
hoặc … we were able to persuade them. (không nói could persuade)

So sánh:

- Jack was an excellent tennis player. He could beat anybody. (= he had the general ability to beat anybody)

nhưng

- Jack and Alf had a game of tennis yesterday. Alf played very well but in the end Jack managed to beat him. hoặc … was able to beat him. (= he managed to beat him in this particular game)

Phủ định của could làcouldn't (could not):

- My grandfather couldn't swim.
- We tried hard but we couldn't persuade them to come with us.
- Alf played well but he couldn't beat Jack.

D. Các bạn xem thêm video về lý thuyết này:

Xem thêm: Can, May, Be able to!

 

[Butchi]

Bài tập thực hành

BÀI TẬP THỰC HÀNH
​

Bài 1: Complete the sentences using can or (be) able to. Use can if possible; otherwise use (be) able to.

1. George has travelled a lot. He...............can.................speak four languages.
2. I haven't .........been able to..............sleep very well recently.
3. Sandra........................................................drive but she hasn't got a car.
4. I can't understand Martin. I've never................................................. understand him.
5. I used to ................................................stand on my head but I can't do it now.
6. I can't see you on Friday but I ...........................................meet you on Saturday morning.
7. Ask Catherine about your problem. She might ............................................ help you.


Bài 2: Write sentences about yourself using the ideas in brackets.

1. (something you used to be able to do)........... I used to be able to sing well............
2. (something you used to be able to do) I used .............................................................................
3. (something you would like to be able to do) I'd.............................................................................
4. (something you have never been able to do) I've............................................................................


Bài 3: Complete the sentences with can/can't/could/couldn't + one of these verbs:

come ..........cat ..........hear ..........run ..........sleep ..........wait

1. I'm afraid I .................can't come..................... to your party next week.
2. When Tim was 16, he was a fast runner. He.........................................100 meters in 11 seconds.
3. Are you in a hurry?' 'No, I've got plenty of time. I ................................................................'
4. I was feeling sick yesterday. I ..................................................... anything.
5. Can you speak up a bit? I ..................................................... you very well.
6. 'You look tired.' 'Yes, I......................................................... last night,'


Bài 4: Complete the answers to the questions with was/were able to.

1 A: Did everybody escape from the fire?
B: Yes. Although the fire spread quickly, everybody...............was able to escape......................
2 A: Did you have difficulty finding Ann's house?
B: Not really. Ann had given us good directions and we ....................................................
3.A: Did you finish your work this afternoon?
B: Yes. There was nobody to disturb me, so ..........................................................
4. A: Did the thief get away?
B: Yes. No one realised what was happening and the thief ................................................................


Bài 5: Complete the sentences using could, couldn't or was/were able to.

1. My grandfather was a very clever man. He..............could............... speak five languages.
2. I looked everywhere for the book but I _couldn't_ find it.
3. They didn't want to come with us at first but we.............were able to................ persuade them.
4. Laura had hurt her leg and ............................................ walk very well.
5. Sue wasn't at home when I phoned but I..............................contact her at her office.
6. I looked very carefully and I....................................... see a figure in the distance.
7. I wanted to buy some tomatoes. The first shop I went to didn't have any but I ................................. get some in the next shop.
8. My grandmother loved music. She.......................................... play the piano very well.
9. A girl fell into the river but fortunately we ......................................... rescue her.
10. I had forgotten to bring my camera so I ....................................... take any photographs.

ĐÁP ÁN

Spoiler

Bài 1

Spoiler

3 can

4 been able to

5 be able to

6 can

7 be able to

Bài 2 Example answers:

2 I used to be able to run fast.

3 I'd like to be able to play a musical instrument.

4 I've never been able to get up early.

Bài 3

2 could run

3 can wait

4 couldn't eat

5 can't hear

6 couldn't sleep

Bài 4

2 were able to find it.

3 I was able to finish it.

4 was able to get away.

Bài 5

4 couldn't/wasn't able to

5 was able to

6 could/was able to

7 was able to

8 could/was able to

9 were able to

10 couldn't/wasn't able to