Modals - English Grammar
1) can
Use
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Examples
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ability to do sth. in the present (substitute form: to be able to)
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I can speak English.
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permission to do sth. in the present (substitute form: to be allowed to)
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Can I go to the cinema?
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request
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Can you wait a moment, please?
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offer
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I can lend you my car till tomorrow.
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suggestion
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Can we visit Grandma at the weekend?
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possibility
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It can get very hot in Arizona.
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2) could
Use
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Examples
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ability to do sth. in the past (substitute form: to be able to)
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I could speak English.
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permission to do sth. in the past (substitute form: to be allowed to)
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I could go to the cinema.
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polite question *
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Could I go to the cinema, please?
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polite request *
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Could you wait a moment, please?
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polite offer *
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I could lend you my car till tomorrow.
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polite suggestion *
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Could we visit Grandma at the weekend?
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possibility *
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It could get very hot in Montana.
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3) may
Use
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Examples
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possibility
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It may rain today.
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permission to do sth. in the present (substitute form: to be allowed to)
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May I go to the cinema?
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polite suggestion
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May I help you?
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4) might
Use
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Examples
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possibility (less possible than may) *
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It might rain today.
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hesitant offer *
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Might I help you?
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5) must
Use
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Examples
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force, necessity
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I must go to the supermarket today.
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possibility
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You must be tired.
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advice, recommendation
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You must see the new film with Brad Pitt.
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6) must not/may not
Use
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Examples
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prohibition
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You mustn't work on dad's computer.
You may not work on dad's computer.
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7) need not
Use
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Examples
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not necessary
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I needn't go to the supermarket, we're going to the restaurant tonight.
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8) ought to
Use
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Examples
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advice
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You ought to drive carefully in bad weather.
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obligation
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You ought to switch off the light when you leave the room.
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9) shall
instead of will in the 1st person
Use
|
Examples
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suggestion
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Shall you pay the bill?
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10) should
Use
|
Examples
|
advice
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You should drive carefully in bad weather.
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obligation
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You should switch off the light when you leave the room.
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11) will
Use
|
Examples
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wish, request, demand, order (less polite than would)
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Will you please shut the door?
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prediction, assumption
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I think it will rain on Friday.
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promise
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I will stop smoking.
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spontaneous decision
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Can somebody drive me to the station? - I will.
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habits
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She's strange, she'll sit for hours without talking.
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12) would
Use
|
Examples
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wish, request (more polite than will)
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Would you shut the door, please?
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habits in the past
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Sometimes he would bring me some flowers.
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* no past forms - future forms
Uses of Shall and Will and Should
In England, shall is used to express the simple future for first person I and we, as in "Shall we meet by the river?" Will wouldbe used in the simple future for all other persons. Using will in the first person would express determination on the part of the speaker, as in "We will finish this project by tonight, by golly!" Using shall in second and third persons would indicate some kind of promise about the subject, as in "This shall be revealed to you in good time." This usage is certainly acceptable in the U.S., although shall is used far less frequently. The distinction between the two is often obscured by the contraction 'll, which is the same for both verbs.
In the United States, we seldom use shall for anything other than polite questions (suggesting an element of permission) in the first-person:
•
"Shall I call a doctor for you?"
(In the second sentence, many writers would use should instead, although should is somewhat more tentative than shall.) In the U.S., to express the future tense, the verb will is used in all other cases.
Shall is often used in formal situations (legal or legalistic documents, minutes to meetings, etc.) to express obligation, even with third-person and second-person constructions:
•
The board of directors shall be responsible for payment to stockholders.
•
The college president shall report financial shortfalls to the executive director each semester."
Should is usually replaced, nowadays, by would. It is still used, however, to mean "ought to" as in
•
You really shouldn't do that.
•
If you think that was amazing, you should have seen it last night.
In British English and very formal American English, one is apt to hear or read should with the first-person pronouns in expressions of liking such as "I should prefer iced tea" and in tentative expressions of opinion such as
•
I should imagine they'll vote Conservative.
•
I should have thought so.
(The New Fowler's Modern English Usage edited by R.W. Burchfield. Clarendon Press: Oxford, England. 1996. Used with the permission of Oxford University Press. Examples our own.)
Uses of Can and Could
The modal auxiliary can is used
•
to express ability (in the sense of being able to do something or knowing how to do something):
He can speak Spanish but he can't write it very well.
•
to expression permission (in the sense of being allowed or permitted to do something):
Can I talk to my friends in the library waiting room? (Note that can is less formal than may. Also, some writers will object to the use of can in this context.)
•
to express theoretical possibility:
American automobile makers can make better cars if they think there's a profit in it.
The modal auxiliary could is used
•
to express an ability in the past:
I could always beat you at tennis when we were kids.
•
to express past or future permission:
Could I bury my cat in your back yard?
•
to express present possibility:
We could always spend the afternoon just sitting around talking.
•
to express possibility or ability in contingent circumstances:
If he studied harder, he could pass this course.
In expressing ability, can and could frequently also imply willingness: Can you help me with my homework?
Can versus May
Whether the auxiliary verb can can be used to express permission or not — "Can I leave the room now?" ["I don't know if you can, but you may."] — depends on the level of formality of your text or situation. As Theodore Bernstein puts it in The Careful Writer, "a writer who is attentive to the proprieties will preserve the traditional distinction: can for ability or power to do something, may for permission to do it.
The question is at what level can you safely ignore the "proprieties." Merriam-Webster's Dictionary, tenth edition, says the battle is over and can can be used in virtually any situation to express or ask for permission. Most authorities, however, recommend a stricter adherence to the distinction, at least in formal situations.
Authority: The Careful Writer by Theodore Bernstein. The Free Press: New York. 1998. p. 87.
Uses of May and Might
Two of the more troublesome modal auxiliaries are may andmight. When used in the context of granting or seeking permission, might is the past tense of may. Might is considerably more tentative than may.
•
May I leave class early?
•
If I've finished all my work and I'm really quiet, might I leave early?
In the context of expressing possibility, may and might are interchangeable present and future forms and might + have + past participle is the past form:
•
She might be my advisor next semester.
•
She may be my advisor next semester.
•
She might have advised me not to take biology.
Avoid confusing the sense of possibility in may with the implication of might, that a hypothetical situation has not in fact occurred. For instance, let's say there's been a helicopter crash at the airport. In his initial report, before all the facts are gathered, a newscaster could say that the pilot "may have been injured." After we discover that the pilot is in fact all right, the newscaster can now say that the pilot "might have been injured" because it is a hypothetical situation that has not occurred. Another example: a body had been identified after much work by a detective. It was reported that "without this painstaking work, the body may have remained unidentified." Since the body was, in fact, identified, might is clearly called for.
Uses of Will and Would
In certain contexts, will and would are virtually interchangeable, but there are differences. Notice that the contracted form 'll is very frequently used for will.
Will can be used to express willingness:
•
I'll wash the dishes if you dry.
•
We're going to the movies. Will you join us?
It can also express intention (especially in the first person):
•
I'll do my exercises later on.
and prediction:
•
specific: The meeting will be over soon.
•
timeless: Humidity will ruin my hairdo.
•
habitual: The river will overflow its banks every spring.
Would can also be used to express willingness:
•
Would you please take off your hat?
It can also express insistence (rather rare, and with a strong stress on the word "would"):
•
Now you've ruined everything. You would act that way.
and characteristic activity:
•
customary: After work, he would walk to his home in West Hartford.
•
typical (casual): She would cause the whole family to be late, every time.
In a main clause, would can express a hypothetical meaning:
•
My cocker spaniel would weigh a ton if I let her eat what she wants.
Finally, would can express a sense of probability:
•
I hear a whistle. That would be the five o'clock train.
