Collins Cobuild English Grammar (110 page)

Using modals

5.92
    Language is not always used just to exchange information by making simple statements and asking questions. Sometimes we want to make requests, offers, or suggestions, or to express our wishes or intentions. We may want to be polite or tactful, or to indicate our feelings about what we are saying.

We can do all these things by using a set of verbs called
modals
. Modals are always used with other verbs. They are a special kind of
auxiliary verb
.

Here is a list of the modals used in English:

can

could

may

might

must

ought to

shall

should

will

would

In some grammars,
dare
,
need
, and
used to
are also referred to as modals. In this grammar, we call these words
semi-modals
. They are dealt with separately in paragraphs
5.246
to
5.256
.

Ought
is sometimes regarded as a modal, rather than
ought to
. For a further note about this, see paragraph
5.99
.

Modals are sometimes called
modal verbs
or
modal auxiliaries
.

5.93
    The main uses of modals are explained in paragraphs
5.94
to
5.98
. Special features of modals are described in paragraphs
5.99
to
5.106
.

Ways of referring to time when using modals are explained in paragraphs
5.107
to
5.114
. Ways of using modals to say whether something is possible are explained in paragraphs
5.115
to
5.151
. Ways of using modals when interacting with other people are explained in paragraphs
5.152
to
5.220
.

Expressions that can be used instead of modals are described in paragraphs
5.221
to
5.245
.
Semi-modals
are explained in paragraphs
5.246
to
5.256
.

The main uses of modals

5.94
    Modals are mainly used when you want to show your attitude towards what you are saying, or when you are concerned about the effect of what you are saying on the person you are speaking or writing to.

attitude to information

5.95
    When you are giving information, you sometimes use modals to show how certain you are that what you are saying is true or correct.

For example, if you say
Mr Wilkins is the oldest person in the village
, you are giving a definite statement of fact. If you say
Mr Wilkins must be the oldest person in the village
, the modal
must
shows that you think Mr Wilkins is the oldest person, because you cannot think of anyone in the village who is older than Mr Wilkins. If you say
Mr Wilkins might be the oldest person in the village
, the modal
might
shows that you think it is possible that Mr Wilkins is the oldest person, because he is very old.

attitude to intentions

5.96
    You can use modals to show your attitude towards the things you intend to do, or intend not to do. For example, if you say
I won’t go without Simon
, you are expressing strong unwillingness to go without Simon. If you say
I can’t go without Simon
, you are saying that there is a special reason for not going without him. If you say
I couldn’t go without Simon
, you are saying that you are unwilling to go without Simon, because to do so would be wrong, or impossible because of the circumstances.

attitude to people

5.97
    When you use language, you are affecting and responding to a particular person or audience. Modals are often used to produce a particular effect, and the modal you choose depends on several factors, such as the relationship you have with your listener, the formality or informality of the situation, and the importance of what you are saying.

For example, it would normally be rude to say to a stranger
Open the door
, although you might say it in an emergency, or you might say it to a close friend or a child. Normally, you would say to a stranger
Will you open the door
?,
Would you open the door
?, or
Could you open the door
?, depending on how polite you want to be.

use in sentences containing more than one clause

5.98
    Modals have special uses in three kinds of sentence containing more than one clause:

they are used in
reported clauses

Wilson dropped a hint that he
might
come.
I felt that I
would
like to wake her up.

For more information about reported clauses see
Chapter 7
.

they are used in
conditional statements

If he had died when he was 50, he
would
have died healthy.
If only things had been different, she
would
have been far happier with George.

For more information about conditionals see paragraphs
8.25
to
8.42
.

they are used in
purpose clauses
.

He stole under the very noses of the store detectives in order that he
might
be arrested and punished.
He resigned so that he
could
spend more time with his family.

For more information about purpose clauses see paragraphs
8.47
and
8.48
.

Special features of modals

form of following verb

5.99
    Modals are followed by the
base form
of a verb.

I must
leave
fairly soon.
I think it will
be
rather nice.
They ought to
give
you your money back.

Note that
ought
is sometimes regarded as a modal, rather than
ought to
.
Ought
is then said to be followed by a
to
-infinitive.

5.100
   Sometimes a modal is followed by the base form of one of the auxiliary verbs
have
or
be
, followed by a participle.

When a modal is followed by
be
and an
-ing
participle, this shows that you are talking about the present or the future.

People
may be watching
.
You
ought to be doing
this.
The play
will be starting
soon.

When a modal is followed by
have
and an
-ed
participle, this shows that you are talking about the past.

You
must have heard
of him.
She
may have gone
already.
I
ought to have sent
the money.

In passive structures, a modal is followed by
be
or
have been
and an
-ed
participle.

The name of the winner
will be announced
.
They
ought to be treated
fairly.
Such charges
may have been justified
.

A modal is never followed by the auxiliary verb
do
, or by another modal.

no inflections

5.101
   Modals do not inflect. This means there is no
-s
form in the third person singular, and there are no
-ing
or
-ed
forms.

There’s nothing I
can
do about it.
I am sure he
can
do it.
I
must
leave fairly soon.

Could
is sometimes thought to be the past tense of
can
. This is discussed in paragraphs
5.110
and
5.111
.

negatives

5.102
   Negatives are formed by putting a
negative word
such as
not
immediately after the modal.
Can not
is usually written as one word,
cannot
.

You
must not
worry.
I
cannot
go back.

In the case of
ought to
, you put the negative word after
ought
.

He
ought not to
have done so.

In American English, the
to
of
ought to
is optional in negative statements.