Ought to, had better, be supposed to
The fine grain of obligation: ought to (moral should), had better (warning), be supposed to (expected but...), needn't
I can shade obligation with ought to, had better, be supposed to and needn't.
Look at these examples. Can you spot the grammar pattern?
We'd better leave now, or we'll be explaining ourselves to the babysitter.
We'd better leave now, or we'll be explaining ourselves to the babysitter.
I'm supposed to be writing my thesis, but the balcony tomatoes needed me.
I'm supposed to be writing my thesis, but the balcony tomatoes needed me.
Pay attention to the highlighted parts. What do they have in common?
Beyond must and should:
| Form | Flavor | Example |
|---|---|---|
| ought to | moral/right thing | You ought to call your parents. |
| had better | or else! (warning) | You'd better hurry - the gate closes at six. |
| be supposed to | expected (often unmet) | I'm supposed to be on a diet. |
| needn't / don't have to | no obligation | You needn't pay - it's on me. |
had better + bare infinitive (no to!); its negative: had better not. be supposed to loves irony: what should happen but doesn't.
- *had better to go → had better go
- needn't/mustn't confused: needn't = no need; mustn't = forbidden
Common Error Patterns
to after had better
had better + bare infinitive
needn't/mustn't collapsed
needn't = no obligation; mustn't = prohibition
We'd better leave now, or we'll be explaining ourselves to the babysitter.
We'd better leave now, or we'll be explaining ourselves to the babysitter.
had better + or-clause: the built-in warning.
I'm supposed to be writing my thesis, but the balcony tomatoes needed me.
I'm supposed to be writing my thesis, but the balcony tomatoes needed me.
be supposed to: the expectation you're dodging.
Practice in course
Apply this grammar in B1 course exercises