ADVICE, RECOMMENDATION & OBLIGATION
Should / ought to / must / have to
These structures differ in strength and in whether the responsibility is advice, a strong necessity or an external requirement.
02LESSON TOPIC
From recommendation to requirement
Should and ought to recommend the sensible or responsible action. Must expresses strong necessity, a rule or a personal obligation. Have to commonly presents an external requirement. Must not expresses prohibition.
MODELYou ought to take notes during the lesson.
We have to upload our assignments by 5 p.m.
| Meaning | Structure | Example |
|---|---|---|
| advice | should + V1 | Students should share their ideas. |
| recommendation | ought to + V1 | You ought to take notes. |
| strong necessity / rule | must + V1 | You must protect your password. |
| prohibition | must not + V1 | You must not share your password. |
| external requirement | have/has to + V1 | We have to upload the task by five. |
Compare:You should save your work. = good advice. You must save your work. = strong necessity. You have to submit it by 5. = an external deadline requires it.