What are "modal auxiliary verbs"?
The verbs can, could, will,
would, should, may, might, must, ought and shall are verbs which 'help' other
verbs to express a meaning: it is important to realise that these "modal
verbs" have no meaning by themselves. A modal verb such as would has
several varying functions; it can be used, for example, to help verbs express
ideas about the past, the present and the future. It is therefore wrong to
simply believe that "would is the past of will": it is many other
things.
A few basic grammatical rules
applying to modal verbs
Modal verbs are NEVER used
with other auxiliary verbs such as do, does, did etc. The negative is formed
simply by adding "not" after the verb; questions are formed by
inversion of the verb and subject:
You should not do that.
Could you pick me up when
I've finished?
Modal verbs NEVER change form: you can never
add an "-s" or "-ed", for example.
Modal
verbs are NEVER followed by to, with the exception of ought to.
What sort of meanings do
modals give to other verbs?
The meaning are usually
connected with ideas of DOUBT, CERTAINTY, POSSIBILITY and PROBABILITY,
OBLIGATION and PERMISSION (or lack of these). You will see that they are not
used to talk about things that definitely exist, or events that definitely
happened. These meanings are sometimes divided into two groups:
DEGREES OF CERTAINTY:
certainty; probability; possibility; impossibility
OBLIGATION/FREEDOM TO ACT:
permission,lack of permission; ability; obligation.
Let's look at each modal verb
separately, and the functions they help to express:
WILL : Making
personal predictions
I don't think the Queen will
ever abdicate.
I doubt if I'll stay here
much longer.
Talking about the present
with certainty (making deductions)
I'm sure you will understand
that there is nothing the Department can do
There's a letter for you.
It'll be from the bank: they said they'd be writing.
Talking about the future with
certainty
I won't be in the office
until 11; I've got a meeting.
Don't bother ringing: they'll
have left for their 10 o'clock lecture.
Talking about the past with
certainty
I'm sure you will have
noticed that attendance has fallen sharply.
Reassuring someone
Don't worry! You'll settle
down quickly, I'm sure.
It'll be all right! You won't
have to speak by yourself.
Making a decision
For the main course I'll have
grilled tuna.
I'm very tired. I think I'll
stay at home tonight.
Making a semi-formal request
Will you open the window,
please? It's very hot in here.
Sign this, will you?
Offering to do something
You stay there! I'll fetch
the drinks.
Insistence; habitual
behaviour
I'm not surprised you don't
know what to do! You will keep talking in class.
Damn! My car won't start.
I'll have to call the garage.
Making a promise or a threat
You can count on me! I'll be
there at 8 o'clock sharp.
If you don't finish your
dinner off, you'll go straight to bed!
SHALL : Shall
is a form of will, used mostly in the first person. Its use, however, is
decreasing, and in any case in spoken English it would be contracted to
"-ll" and be indistinguishable from will.
The only time you do need to
use it is in questions, when:
Making offers
Shall I fetch you another
glass of wine?
Making suggestions
Shall we go to the cinema
tonight?
MAY & MIGHT : May & might sometimes have virtually the same meaning; they are
used to talk about possibilities in the past, present or future.
("Could" is also sometimes used).
May is sometimes a little bit
"more sure" (50% chance); whereas might expresses more doubt (maybe
only a 30% chance).
May & might are used,
then, for:
Talking about the present or
future with uncertainty
She may be back in her
office: the lecture finished ten minutes ago.
I may go shopping tonight, I
haven't decided yet.
England might win the World
Cup, you never know.
Talking about the past with
uncertainty
I'm surprised he failed. I
suppose he might have been ill on the day of the exam.
They can also sometimes be
used for talking about permission, but usually only in formal situations.
Instead of saying May I open a window? we would say Is it all right/OK if I
open a window? or Can I open a window? for example. You might, however, see:
Students may not borrow
equipment without written permission.
MAY : Talking
about things that can happen in certain situations
If the monitors are used in
poorly lit places, some users may experience headaches.
Each nurse may be responsible
for up to twenty patients.
With a similar meaning to
although
The experiment may have been
a success, but there is still a lot of work to be done. (= Although it was a
success, there is still ...)
MIGHT : Saying
that something was possible, but did not actually happen
You saw me standing at the
bus stop! You might have stopped and given me a lift!
WOULD : As
the past of will, for example in indirect speech
"The next meeting will
be in a month's time" becomes
He said the next meeting
would be in a month's time.
Polite requests and offers (a
'softer' form of will)
Would you like another cup of
tea?
Would you give me a ring
after lunch?
I'd like the roast duck,
please.
In conditionals, to indicate
'distance from reality': imagined, unreal, impossible situations
If I ruled the world, every
day would be the first day of Spring.
It would have been better if
you'd word processed your assignment.
After 'wish', to show regret
or irritation over someone (or something's) refusal or insistence on doing
something (present or future)
I wish you wouldn't keep
interrupting me.
I wish it would snow.
(This is a complicated area!
Check in a good grammar book for full details!)
Talking about past habits
(similiar meaning to used to)
When I was small, we would
always visit relatives on Christmas Day.
Future in the past
The assassination would become
one of the key events of the century.
CAN & COULD : Talking about ability
Can you speak Mandarin?
(present)
She could play the piano when
she was five. (past)
Making requests
Can you give me a ring at
about 10?
Could you speak up a bit
please? (slightly more formal, polite or 'softer')
Asking permission
Can I ask you a question?
Could I ask you a personal
question? (more formal, polite or indirect)
Reported speech
Could is used as the past of
can.
He asked me if I could pick
him up after work.
General possibility
You can drive when you're 17.
(present)
Women couldn't vote until
just after the First World War.
Choice and opportunities
If you want some help with
your writing, you can come to classes, or you can get some 1:1 help.
We could go to Stratford
tomorrow, but the forecast's not brilliant. (less definite)
Future probability
Could (NOT can) is sometimes
used in the same way as might or may, often indicating something less definite.
When I leave university I
might travel around a bit, I might do an MA or I suppose I could even get a
job.
Present possibility
I think you could be right
you know. (NOT can)
That can't be the right
answer, it just doesn't make sense.
Past possibility
If I'd known the lecture had
been cancelled, I could have stayed in bed longer.
MUST : Examples
here refer to British English; there is some variation in American English.
Necessity and obligation
Must is often used to
indicate 'personal' obligation; what you think you yourself or other people/things
must do. If the obligation comes from outside (eg a rule or law), then have to
is often (but not always) preferred:
I really must get some
exercise.
People must try to be more
tolerant of each other.
You musn't look - promise?
If you own a car, you have to
pay an annual road tax.
Strong advice and invitations
I think you really must make
more of an effort.
You must go and see the film
- it's brilliant.
You must come and see me next
time you're in town.
Saying you think something is
certain
This must be the place -
there's a white car parked outside.
You must be mad.
What a suntan! You must have
had great weather.
The negative is expressed by
can't:
You're going to sell your
guitar! You can't be serious!
She didn't wave - she can't
have seen me.
Top of page
SHOULD : Giving
advice
I think you should go for the
Alfa rather than the Audi.
You shouldn't be drinking if
you're on antibiotics.
You shouldn't have ordered
that chocolate dessert - you're not going to finish it.
Obligation: weak form of must
The university should provide
more sports facilities.
The equipment should be
inspected regularly.
Deduction
The letter should get to you
tomorrow - I posted it first class.
Things which didn't or
may/may not have happened
I should have renewed my TV
licence last month, but I forgot.
You shouldn't have spent so
much time on that first question.
Ought to
Ought to usually has the same
meaning as should, particularly in affirmative statements in the present:
You should/ought to get your
hair cut.
Should is much more common
(and easier to say!), so if you're not sure, use should.
Exercises – All Modals
Fill in the blanks with the
correct form of the following modals:
can, could, be able to, may,
might, shall, should, must, have to, don’t
have to, need to
– You may have to make the modals negative according to
the context of the sentence.
– There may be more than one possibility.
He has to take his car to be
serviced. The brakes are squeaking.
Would you please save me a
seat at the dinner event.
If you are sick, you ________
go to work. You’ll infect everyone there.
Drivers _______ stop at red
lights.
You _______ finish the
proposal today. You can finish it tomorrow.
She ______ hear much better
with her new hearing aids.
______ I order us a bottle of
wine?
Sam ______ pick his daughter
up from school. She’s taking the bus home.
You _____________ smoke here.
It’s a smoke-free building.
You ________ eat so many
sweets. They are bad for you.
_________ you mind walking a
little faster? We’re going to be late.
I’m
sorry. I _______ help you. I don’t know how to do it.
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