Modal Verbs of Advice If you want to ask or give advice to someone, we use should or had better.
should 'Should' is the most common way to give advice. S + should / shouldn't + verb He should see his teacher. We shouldn't go to school today. We should take a holiday this year. Question + should + S + verb What should I bring to the park? When should we have the surprise party for Greg? Should I go to Vietnam next year?
had better 'Had better' can be used to give more formal advice, where something negative might happen if we are not to follow the advice. S + had better / hadn't better + verb Peter had better hurry up if he doesn't want to be late for the meeting. (his boss will be angry with him) They had better finish their project soon. (they might get points deducted for missing the deadline) She had better write him a letter explaining the problem. (he might understand more if she writes to him)
Modal Verbs of Ability Modal verbs of ability tell us what someone or something is able to do. For this, we use can or be able to.
can 'Can' is used to speak about abilities- what someone can/can't do on a daily basis and in specific situations. S + can / can't (can not) + verb They can play soccer very well. Mark can't understand French. Birds can fly. Question + can + S + verb Where can I find a bandage for my cut? Can you speak English? When can I speak to the manager?
be able to 'Be able to' conjugates the main verb 'be' instead of the a modal verb. S + be + able to + verb David is able to work six hours days per day. I am not able to come to the party tomorrow night. She is able to speak three languages.
Question+ be + S + able to + verb When are you able to come next month? Is she able to help us on the project? What are you able to do?
Modal Verbs of Permission 'Can' and 'May' are both used to ask for and deny permission to do something.
can S + can / can't (can not) + verb She can stay with us. They can't use those tools. I'm sorry. We can use their lawnmower. Can + S + verb When using 'can' to ask for permission, do not use question words such as 'what', 'where', etc. Can I use your internet? Can I have something to drink please? Can we use your car today?
May/ Could These are a much more polite version of 'can' when asking for permission. It is not commonly used in the negative form (may not), and it is usually used with the pronoun 'I'. Could I use your telephone? May I ask him a few questions?
May I leave now?
Modal Verbs of Obligation Modal verbs of obligation are used to speak about something that is required, or to give something urgency.
must Use 'must' to speak about strong personal obligation at the moment of speaking. S + must + verb The test is tomorrow, I must study! She must finish her homework before twelve. I must speak to Ann today. It's really important. s + mustn't (must not) + verb The negative 'mustn't' is used to speak about actions that are not allowed. She mustn't play with those toys. We mustn't leave before the end of the class. They mustn't use the computers.
Have to 'Have to' is used to speak about daily responsibilities. S + have to + verb She has to get up at seven every morning. They have to deliver pizzas on time. We have to finish the project soon.
(?) + Auxiliary Verb + S + have to + verb Does she have to work on this project with me? Where do we have to go this afternoon? When does Mary have to get up?