• We use can + infinitive
• For example: I can speak English.
(-) I can’t speak English.
(?) Can you speak English?
• Sometimes could is the past of can
• I could hear something.
• We use could to say that something is possible now or in the future.
• The phone is ringing. It could be Tim.
• Could (do) could have (done)
• I’m so tired. I could sleep for a week (now)
• I was so tired. I could have slept for a week. (past)
4. (be) able to
• (be) able to… is possible instead can.
• I am able to speak any foreign language. (present)
• We use (be) able to in a particular situation
• He was able to beat him. (past)
5. May & Might
• We use may or might to say that something is possibility.
• It may be true.
• It might be true.
• We use may or might to talk about possible actions or happenings in the future.
• I may go to Ireland.
• We use only might when the situation is not real.
• If I knew them better, I might invite them to dinner.
6. Must & Have to
• You can use must to talk about the present or future, but not the past.
• We must go now.
• We must go tomorrow.
• You can use have to in all forms.
• I had to go to the hospital (past)
• Have you ever had to go to hospital? (present perfect)
• We use must or have to to say that it is necessary to do something.
• I must go
• I have to go.
• You can use should to give advice or opinion.
• You look tired. You Should go to bed.
• Should is not as strong as must.
• You should apologies.
• You must apologies. (you have no alternative)