Content introduction modal verbs can 11 may 18

Improbability


E.g. It can’t be true. (Это не может быть правдой. Вряд ли это так.)
In this meaning can is found only in negative sentences, which are often emotionally colored. Depending on the time reference, this can is also used with different forms of the infinitive/

E.g. He can’t be really ill.

She can’t be telling lies.

He can’t have said it.

She can’t have been at home all this time.

She can’t have been waiting for us so long.
Could is also used in this way making the statement less categorical

E.g. It couldn’t be true.

She couldn’t be telling lies.

He couldn’t have said it.

She couldn’t have been at home all this time.

She couldn’t have been waiting for us so long.
Can and could followed by different forms of the infinitive, are found in special questions where they are used for emotional coloring (to express puzzlement, impatience, etc.).

E.g. What can (could) he mean?

What can (could) he be doing?

What can (could) he have done?

Where can (could) he have gone to?

It can be rendered in Russian as: Что, собственно, он имеет в виду?

As is seen from the above examples, the form could referring to present is sometimes clearly opposed to can in that it expresses unreality whereas can expresses reality. This may be observed in the following meanings:

ability – He can speak English. He could speak English if necessary.