ملخص الدرس / الرابعة متوسط/اللغة الإنجليزية/File 2/Using “can”, “could”, “be able to”

We use can + infinitive of the verb (without to) to say that someone has the ability to do something.

eg: I can swim

She can ride a horse.

We also use be able to to express ability.

eg: I am able to swim.

She is able to ride a horse.

Could is the past of can.

eg: My grandfather could read without glasses until he was seventy.

We use could to say that it was possible to do something; it expresses only ability.

Compare could and was able to

eg: a) He could speak 5 foreign languages.

b) The fishing boat sank, but the fisherman

was able to reach the shore. In example (a), we are saying that it was possible for him to speak five foreign languages; Could expresses only his ability to speak foreign languages.

In example (b), we are saying that he managed to reach succeeded reaching the shore in a particular situation.

Was able to expresses a past ability and a past

achievement (achievement means: something done, usually something which needs effort). In this example, it is impossible to use could.