oxford_guide_to_english_grammar

PAGE 119 94 Permission
2 Had better
We also use had better to say what is the best thing to do in a particular situation.
You're ill. You had better see a doctor, NOT You have better see a doctor.
I'd better tidy this room up.
Had better is stronger than should or ought to, although it is not as strong as must.
I'd better tidy up means that I am going to tidy up, because it is the best thing to do.
The negative is had better not.
Come on. We'd better not waste any time.
NOTE
With had better we normally use an indirect question rather than a direct one.
Do you think I'd better call a doctor?
3 Be supposed to
We use be supposed to for what people expect to happen because it is the normal
way of doing things or because it has been ordered or arranged.
When you've paid, you're supposed to take your receipt to the counter over
there. ~ Oh, I see.
Is this food supposed to be kept cool? ~ Yes, put it in the fridge.
This jacket is supposed to have been cleaned, but it looks dirty.
You weren't supposed to mention my secret. ~ Oh, sorry.
We can also use be supposed to for what people say.
Too much sugar is supposed to be bad for you.
94 Permission: can, could, may, might and be
allowed to
1 Giving and refusing permission
a
b
We use can or may to give permission. May is formal and used mainly in writing.
You can use my phone if you like. Anyone can join the club.
Any person over 18 years may/can apply to join the club.
We use the negative forms cannot/can't and may not to refuse permission.
I'm afraid you can't just walk in here.
Customers may not bring their own food into this cafe.
NOTE
Here are some other ways of refusing permission.
Tourists must not take money out of the country. • 92(4c)
Smoking is prohibited/is not permitted on school premises.
No picnics. (mainly written)
2 Asking permission
We use can, could or may to ask permission.
Can I take your umbrella? ~ Of course you can.
Could I borrow this calculator, please? ~ Well, I need it actually.
May we come in?~ Of course.