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have to take an exam in June.
I have got to take/I've got to take an exam in June.
Have to is common in both formal and informal English, but have got to is informal.
b We use got only in simple tenses, but have to has all the forms of an ordinary verb.
Father was so ill we were having to sit up with him night after night.
I don't want to have to punish you.
We cannot use got here.
PAGE 117 92 Necessity
In the past simple had to is more usual than had got to.
I couldn't go to the dance. I had to finish my project.
c With have to, we use do in negatives and questions.
We don't have to pay. Does the winner have to make a speech?
With have got to, we use have as an auxiliary.
We haven't got to pay. Has the winner got to make a speech?
For American English, • 303(5c).
In past simple negatives and questions we almost always use did... have to, not
had... got to.
Did you have to wait long?
3 No necessity
a Needn't and don't have to
We use needn't and don't have to/haven't got to to say that something is
unnecessary.
You need not always make an appointment.
You do not always have to make an appointment.
Often we can use either form. But there is a difference similar to the one between
must and have (got) to. With needn't, the lack of necessity is felt by the speaker.
With don't have to, it results from the situation.
You needn't take me to the station. I can walk.
You don't have to take me to the station. Alan's giving me a lift.
b Need as an ordinary verb
Need to means the same as have to.
The colours have to/need to match.
The figure doesn't have to/doesn't need to be exact.
NOTE
a Americans use don't/doesn't need to, not needn't. • 303(9)
b For This carpet needs cleaning, • 113(1).
c We can also use need as a noun, especially in the phrase no need.
There's no need to get up early.
c Needn't have done and didn't need to
We use these forms to talk about an unnecessary past action. If something
happened which we now know was unnecessary, we usually use needn't
have done.
We needn't have made these sandwiches. No one's eaten any.
(We made them, but it wasn't necessary.)
Didn't need to usually means that the action did not happen.
We didn't need to make any sandwiches. We knew that people were bringing
their own. (We didn't make them because it wasn't necessary.)
But we can also use didn't need to for something unnecessary that actually
happened.
We didn't need to make these sandwiches. No one's eaten any.
We can also use didn't have to.
Fortunately we didn't have to pay for the repairs.
12 MODAL VERBS PAGE 118
4 Necessity not to do something
a We use mustn't to tell someone not to do something.
You mustn't forget your railcard. We mustn't lose this game.
The meaning is the same as Don't forget your railcard. The speaker feels the
necessity. Compare You must remember your railcard.
b Mustn't has a different meaning from needn't/don't have to. Compare these
sentences.
I needn't run. I've got plenty of time.
I mustn't run. I've got a weak heart.
c We can use mustn't or may not to forbid something.
Students must not/may not use dictionaries in the examination.
Here the speaker or writer is the authority, the person who feels the necessity to
stop the use of dictionaries. But if we are talking about rules made by other people,
we use can't or be allowed to. • 94(3)
We can't use/We aren't allowed to use dictionaries in the exam.
93 Obligation and advice: should, ought to etc
1 Should and ought to
a We use should and ought to for obligation and advice, to say what is the right thing
or the best thing to do.
They should build/ought to build more hospitals.
People shouldn't leave/oughtn't to leave litter all over the place.
You should go I ought to go to York. It's an interesting place.
I shouldn't leave/oughtn't to leave things until the last moment.
Who should we invite?/ Who ought we to invite
1
.
Should and ought to are not as strong as must.
You should tour in a group. (It's a good idea to.)
You must tour in a group. (It's essential.)
But in formal rules should is sometimes a more polite and less emphatic
alternative to must.
Passengers should check in at least one hour before departure time.
b We can use the continuous or perfect after should and ought to.
I should be doing some work really.
You should have planted these potatoes last month.
After all the help Guy has had, he ought to have thanked you.
The perfect here means that the right action did not happen. Compare had to,
where the action really happened.
I ought to have left a tip.
(Leaving a tip was the right thing to do, but I didn't leave one.)
I had to leave a tip.
(It was necessary to leave a tip, so I did leave one.)
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 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.
b 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.
12 MODAL VERBS PAGE 120
Here could means a more distant possibility than can and so is less direct, more
tentative. May is rather formal.
NOTE
We can also use might to ask permission, but it is both formal and tentative.
I was wondering if I might borrow your car for the afternoon.
3 Talking about permission
a We sometimes talk about permission when we are not giving it or asking for it. To
do this, we can use can referring to the present or the future and could referring to
the past.
I can stay up as late as I like. My parents don't mind.
These yellow lines mean that you can't park here.
At one time anyone could go and live in the USA.
We cannot use may here because we are not giving or asking permission.
NOT I may stay up late.
b We can also use be allowed to.
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