2. Decide whether these sentences are true or false.

Giving instruction

Use the imperative to tell people what to do or not to do. E.g.: Eat regularly. Don’t smoke.

Giving advice

Use should to say what the right/best thing to do is. E.g.: You should often exercise your listening skills. Use shouldn’t to say what isn’t the right / best thing to do. E.g.: You shouldn’t speak so aloud. Use I think it’s a good idea…, Why don’t you..., I don’t think it’s a good idea to…to give advice. E.g.: I think it’s a good idea to start with this exercise.

Can / can’t, must / mustn’t, could / couldn’t, might / mightn’t, have to, ought to / ought not

Use can to give permission. E.g.: You can listen to music.

Use can’t to refuse permission. E.g.: You can’t keep pets in your room.

Use must to tell someone to do something. E.g.: You must clean your room.

Use mustn’t to tell someone not to do something. E.g.: You mustn’t smoke at home.

Use could to express possibility or past ability as well as to make suggestions and requests. “Could” is also commonly used in conditional sentences as the conditional form of “can.” E.g.: Extreme rain could cause the river to flood the city (possibility) I could run ten miles in my twenties. (past ability); E.g.: You could spend your vacation in Hawaii. (suggestion); E.g.: Could I have something to drink? (polite request)

Use couldn’t to say that it is impossible for something to happen. Jack could not have the key. (it is impossible that he has the key)

Use may to ask permission or suggest something is possible. E.g.: May I borrow your pen? It may rain later today.

Use might to suggest a small possibility of something. E.g.: She might be at home.

Use might not to suggest you do not know if something happens. E.g.: I might not go.

Use have to, to say that something is obligatory. E.g.: Children have to go to school.

Use ought to, to advise or make recommendations. “Ought to” also expresses assumption or expectation as well as strong probability, often with the idea that something is deserved. E.g.: You ought to stop smoking.

Use ought not (without “to”) to advise against doing something, although Americans prefer the less formal forms “should not” or “had better not.” E.g.: John ought not drink so much.

Use had better plus the infinitive without “to” to give advice in the present or future time. E.g.: You’d better tell her everything. The negative form is had better not E.g.: You’d better not come. Use had better to give advice about specific situations, not general ones, you must use should E.g.: You shouldn’t listen to negative people. Use had better to give suggestion that if the advice is not followed, that something bad will happen E.g.: You’d better do what I say or else you will get into trouble.