Possible and probable

Possibility:

·       Possible – means-it has the potential or the power. It refers to what can be done, what can occur or what can be true.

E.g.,

Will it be possible for you to come and see me tomorrow? ( Can you come and see me tomorrow?)

·       Probable refers to what is likely to be done, to occur, or to be true.

*When we say something is probable, we are more confident about its happening, than when we say something is possible.

·       We also use could, might and may to show that something is possible in the future, but not certain.

E.g.,

We may go to a movie tomorrow.

They might buy that house.

If we don’t hurry, we could miss the train.

Probability:

·       We use must / should  to show that we are sure that something is true and we have reasons for our belief:

E.g.,

It must be a good movie. The reviews are good.

He should know. He was there when the accident occurred.

·       We use must have/ should have  for the past:

E.g.,

She must have passed the examination. She looks quite happy.

It's nearly eleven o'clock. They should have arrived  by now.