OBLIGATION MUST HAVE TO SHOULD PRESENT FUTURE PAST
OBLIGATION: MUST HAVE TO SHOULD
PRESENT/ FUTURE PAST EXAMPLES MUST: Subject+ must + verb _______ You must go now. I must call my sister tomorrow. HAVE TO (external): Subject + have to + verb (past obligation is expressed with had to) HAD TO: Subject + had to + verb Children have to go to school. I had to work on New Year’s Eve. SHOULD: SHOULD Subject + should + HAVE + Past You should tell verb participle: them the truth. (Should is weaker than Subject + You should have must/have to. It is should + have told them the used to give advice to + past truth. someone or to say that participle (to something is a good express idea) unfulfilled past obligation)
PROHIBITION: MUSTN’T ABSENCE OF OBLIGATION “IT’S NOT NECESSARY”: DON’T HAVE TO
PRESENT / FUTURE PAST MUSTN’T: ______ Subject + mustn’t (past prohibition is with + verb (to expressed was/were not allowed something that’s not allowed or permitted) CAN’T (external): Subject + can’t + verb or I mustn’t eat so much sugar. You mustn’t park your car outside the shop. COULDN’T I was not allowed to/ Subject + couldn’t park outside the shop. + verb DON’T HAVE TO: DIDN’T HAVE TO: Subject + don’t/doesn’t have Subject + didn’t to + verb (means have to + verb that something is not necessary, but you can do it if you want to) EXAMPLES You don’t have to come to class tomorrow. I didn’t have to wear a uniform at school.
- Slides: 4