Ability: can, could and be able to

A Can and can't

Vicky: How many instruments can you play, Natasha?

Natasha: Three - the violin, the clarinet and the piano.

Vicky: That's terrific. You haven't got a piano here, though.

Natasha: No, but I can go to the music room in college and play the one in there.

Vicky: I'm not musical at all. I can't even sing.

We use can to say that something is possible: that someone has an ability (Natasha can play the piano) or an opportunity (She can go to the music room). Can is usually pronounced but sometimes we say . The negative is cannot or can't .

B Can and be able to

In the present tense, be able to is a little more formal and less usual than can.

Emma is good with computers. She can write/is able to write programs.
But in some structures we always use be able to, not can.
To-infinitive: It's nice to be able to go to the opera, (not to-can-go)

After a modal verb: Melanie might be able to help us.
Present perfect: It's been quiet today. I've been able to get some work done.

For the future we use can or will be able to but not will-can.

If we earn some money, we can go/we'll be able to go on holiday next summer.

I'm afraid I can't come/I won't be able to come to the disco on Friday. But to suggest a possible future action, we normally use can.

Let's have lunch together. We can go to that new restaurant.

C Could and was/were able to

For ability or opportunity in the past, we use could or was/were able to.

Natasha could play (or was able to play) the piano when she was four.

In those days we had a car, so we could travel (or were able to travel) very easily.

To say that the ability or opportunity resulted in a particular action, something that really happened,we use was/were able to but not could.

The plane was able to take off at eleven o'clock, after the fog had lifted.

Luckily Mark was able to get (or succeeded in getting) the work done in time.

The drivers were able to stop (or managed to stop) before they crashed into each other.

Compare these two sentences.

The children could swim when they were quite The children were able to swim across the river.

young, (a past ability) (a past action)

In negative sentences and questions, we can use either form. It was foggy, so the plane couldn't/wasn't able to take off. The pool was closed, so they couldn't/weren't able to have a swim. Could you/Were you able to describe the man to the police?

We normally use could (not was/were able to) with verbs of seeing etc, and with verbs of thinking. We could see the village in the distance. As soon as Harriet opened the door, she could smell gas. I couldn't understand what was happening.

► He can walk on his hands.

1…………………………………………………………………………..3…………………………………………………………………………………..

2…………………………………………………………………………..4………………………………………………………………………………….. ...........

2 Can and be able to (B)

Harriet is visiting David, who hurt himself when he fell off a ladder. Complete the conversation using can

or a form of be able to. Sometimes there is more than one possible answer.

Harriet: Hello, David. I'm sorry I haven't (►) been able to come (come) and see you before.

I've been really busy lately. How are you?
David: I'm OK, thanks. (1)………………………………………. (I / walk) around now.

The doctor says (2) ....................................................... (I / go) back to work soon.

It'll be nice (3)..................................................... ….. (get) out again. I hate being stuck here like this.

I haven't (4)…………………….......................... (do) anything interesting.

3 Could and was/were able to (C)

► Which is closer to the meaning of the sentence 'Years ago I could run a marathon'?

a) I ran a marathon at one particular time in the past.

b) I was once fit enough to run a very long way.

1 Which of these sentences is correct?

I was ill, so I couldn't go to the party.

I was ill, so I wasn't able to go to the party.

a) Only the first one. b) Only the second one. c) Both of them.

2 Which is closer to the meaning of the sentence 'Sarah was able to leave work early yesterday'?

a) Sarah left work early yesterday.

b) Sarah had the opportunity to leave work early yesterday, but we don't know if she took it.

4 Could and was/were able to (C)

Put in could or was/were able to. Sometimes either is possible. Use a negative if necessary.

► Suddenly all the lights went out. We couldn't see a thing.

1 The computer went wrong, but luckily Emma………………………… put it right again.

2 There was a big party last night. You………………………… hear the music half a mile away.

3 I learnt to read music as a child. I......................................... read it when I was five.

4 People heard warnings about the flood, and they............................. move out in time.

5 The train was full. I ............................ find a seat anywhere.

Date: 2014-12-22; view: 3086