Can VS Be able to

[Ov28]

Is there any difference of nuance between them?
I've been taught that can is equal to be able to my English class.
However, I'm not sure this is true or not.
Thanks in advance.

 

[louhevly]

Is there any difference of nuance between them?
I've been taught that can is equal to be able to my English class.
However, I'm not sure this is true or not.
Thanks in advance.

"can" is often equivalent to the present or future tenses of "be able to" (exs.: I can swim = I am able to swim; I can pay you tomorrow = I will be able to pay you tomorrow = I'm going to be able to pay you tomorrow). In these cases it expresses ability. But it can also be used with impersonal subjects to express possibility: "Crime can be a problem in pioneer communities", and in these cases I don't think we can say *Crime is able to be a problem...*.

You can also use "can" to ask permission: "Can I help you?"

There's also the expression "you/I can tell", meaning "it is evident": "You can tell she's Irish from her accent".

HTH,
Lou

 

[Ov28]

Thank you very much louhevly.
I understood there's no difference of meaning when it's used as the meaning of ability.
If you don't mind, I'd like to know whether the difference has something with politness and formality or not as well.
Thanka in advance.

 

[louhevly]

Thank you very much louhevly.
I understood there's no difference of meaning when it's used as the meaning of ability.
If you don't mind, I'd like to know whether the difference has something with politness and formality or not as well.
Thanka in advance.

No. "can" is almost always used simply because it is easier to say.

 

[Ov28]

No. "can" is almost always used simply because it is easier to say.

OK, I got it. Much appreciated louhevly.