Learn English – Could have arrived now

grammar

Please tell me if the following sentences are the same or not?

  1. It is ten o’clock. They could have arrived now.

  2. It is ten o’clock. They could have arrived by now.

Are they same? If not, then please tell me what the difference between them is.

Thank you.

Best Answer

First of all, it's unusual to use the word could in this context- it would mean that it is possible that they have already arrived, but you don't know for certain. If that's what you meant, both sentences are correct, but the second is more idiomatic.

If you meant that you expected them to arrive before now, then should is the correct word to use.

It is ten o’clock. They should have arrived now.

This means that you expect that they have arrived, but you don't know for certain whether they have arrived.

It is ten o’clock. They should have arrived by now.

This means that you expected them to have arrived, but you know that they have not yet arrived- you are expressing concern that things are not going according to plan.