Modal Verbs of Probability

Modal Verbs of Probability
We can use these modal verbs (also called modals of deduction, speculation or certainty) when we want to make a guess about something. We choose the verb depending on how sure we are.
Talking about the present:
must / might / could / may / can t + infinitive
For example:
I am waiting for Julie with another friend, David.
I ask: Where is Julie?
David guesses:
• She must be on the bus. (I m fairly sure this is a good guess)
• She might come soon. (maybe)
• She could be lost. (maybe)
• She may be in the wrong room. (maybe)
• She can t be at home. (I m fairly sure this isn t true)
Notice that the opposite of must is can t in this case.
• He could have overslept.
We can also choose to use might have + past participle to mean the same thing:
• He might have got stuck in traffic.
• He might have forgotten that we were meeting today.
• He might have overslept. We could use "could" : He could have got stuck in traffic. He could have forgotten that we were meeting today.
He could have overslept.