Definition of Modal Auxiliary
An auxiliary verb (as can, must,
might, may) that is characteristically used with a verb of predication and
expresses a modal modification and that in English differs formally from other
verbs in lacking -s and -ing forms .
The Kinds of Auxiliary
Helping verbs or auxiliary verbs
such as will, shall, may, might, can, could, must, ought to, should, would,
used to, need are used in conjunction with main verbs to express shades of
time and mood. The combination of helping verbs with main verbs creates what
are called verb phrases or verb strings. In the following sentence, “will have
been” are helping or auxiliary verbs and “studying” is the main verb; the whole
verb string is underlined :
- As of next August, I will have been studying
chemistry for ten years.
Students should remember that
adverbs and contracted forms are not, technically, part of the verb. In the
sentence, “He has already started.” the adverb already modifies the verb, but
it is not really part of the verb. The same is true of the ‘nt in “He
hasn’t started yet” (the adverb not, represented by the contracted n’t,
is not part of the verb, has started).
Shall, will and forms of have, do and be combine with
main verbs to indicate time and voice. As auxiliaries, the verbs be, have
and do can change form to indicate changes in subject and time.
- I shall go now.
- He had won the election.
- They did write that novel together.
- I am going now.
- He was winning the election.
- They have been writing that novel for a long
time.
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 would be 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 we go now?”
- “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.
Uses
of Do, Does and Did
In the simple present tense, do
will function as an auxiliary to express the negative and to ask questions.
(Does, however, is substituted for third-person, singular subjects in
the present tense. The past tense did works with all persons, singular
and plural.)
- I don’t study at night.
- She doesn’t work here anymore.
- Do you attend this school?
- Does he work here?
These verbs also work as “short
answers,” with the main verb omitted.
- Does she work here? No, she doesn’t
work here.
With “yes-no” questions, the form of
do goes in front of the subject and the main verb comes after the
subject:
- Did your
grandmother know Truman?
- Do
wildflowers grow in your back yard?
Forms of do are useful in
expressing similarity and differences in conjunction with so and neither.
- My wife hates spinach and so does my son.
- My wife doesn’t like spinach; neither do I.
Do
is also helpful because it means you don’t have to repeat the verb:
- Larry excelled in language studies; so did his
brother.
- Raoul studies as hard as his sister does.
The so-called emphatic do has
many uses in English.
- To add emphasis to an entire sentence: “He does
like spinach. He really does!”
- To add emphasis to an imperative: “Do come in.”
(actually softens the command)
- To add emphasis to a frequency adverb: “He never did
understand his father.” “She always does manage to hurt her
mother’s feelings.”
- To contradict a negative statement: “You didn’t do your
homework, did you?” “Oh, but I did finish it.”
- To ask a clarifying question about a previous negative
statement: “Ridwell didn’t take the tools.” “Then who did take the
tools?”
- To indicate a strong concession: “Although the Clintons
denied any wrong-doing, they did return some of the gifts.”
In the absence of other modal
auxiliaries, a form of do is used in question and negative constructions
known as the get passive:
- Did
Rinaldo get selected by the committee?
- The audience didn’t get riled up by the
politician.
Uses
of Have, Has and Had
Forms of the verb to have are
used to create tenses known as the present perfect and past perfect.
The perfect tenses indicate that something has happened in the past; the
present perfect indicating that something happened and might be continuing to
happen, the past perfect indicating that something happened prior to something
else happening. (That sounds worse than it really is!) See the section on Verb
tenses in the activevoice for further explanation; also review material in the Directory
of English tenses
To have is also in combination with other modal verbs to express
probability and possibility in the past.
- As an affirmative statement, to have can express
how certain you are that something happened (when combined with an
appropriate modal + have + a past participle): “Georgia must have
left already.” “Clinton might have known about the gifts.” “They may have
voted already.”
- As a negative statement, a modal is combined with not
+ have + a past participle to express how certain you are that
something did not happen: “Clinton might not have known about the gifts.”
“I may not have been there at the time of the crime.”
- To ask about possibility or probability in the past, a
modal is combined with the subject + have + past participle: “Could
Clinton have known about the gifts?”
- For short answers, a modal is combined with have:
“Did Clinton know about this?” “I don’t know. He may have.” “The evidence
is pretty positive. He must have.”
To have (sometimes combined with to get) is used to express
a logical inference:
- It’s been raining all week; the basement has to be
flooded by now.
- He hit his head on the doorway. He has got to be over
seven feet tall!
Have is often combined with an infinitive to form an auxiliary
whose meaning is similar to “must.”
- I have to have a car like that!
- She has to pay her own tuition at college.
- He has to have been the first student to try that.
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.
Uses
of May and Might
Two of the more troublesome modal
auxiliaries are may and might. 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.
Uses
of Used to
The auxiliary verb construction used
to is used to express an action that took place in the past, perhaps
customarily, but now that action no longer customarily takes place:
- We used to take long vacation trips with the whole
family.
The spelling of this verb is a
problem for some people because the “-ed” ending quite naturally disappears in
speaking: “We yoostoo take long trips.” But it ought not to disappear in
writing. There are exceptions, though. When the auxiliary is combined with
another auxiliary, did, the past tense is carried by the new auxiliary
and the “-ed” ending is dropped. This will often happen in the interrogative:
- Didn’t you use to go jogging every morning before
breakfast?
- It didn’t use to be that way.
Used to can also be used to convey the sense of being accustomed to
or familiar with something:
- The tire factory down the road really stinks, but we’re
used to it by now.
- I like these old sneakers; I’m used to them.
Used to is best reserved for colloquial usage; it has no place in
formal or academic text.
Exercise
Fill these blanks using modal : can
could have to must
might should
Top of Form
- Ted’s flight from Amsterdam took more than 11 hours. He
be exhausted after such a long flight. He prefer to stay in tonight and
get some rest.2. If you want to get a better feeling for how the city is
laid out, you walk downtown and explore the waterfront.
- Hiking the trail to the peak be dangerous if you are
not well prepared for dramatic weather changes. You research the route a
little more before you attempt the ascent.4. When you have a small child
in the house, you leave small objects lying around. Such objects be
swallowed, causing serious injury or even death.
5. Dave:
you hold your breath for more than a minute?
Nathan: No, I can’t.
6. Jenny’s
engagement ring is enormous! It have cost a fortune.
7. Please
make sure to water my plants while I am gone. If they don’t get enough water,
they die.
8. I speak
Arabic fluently when I was a child and we lived in Egypt. But after we moved
back to Canada, I had very little exposure to the language and forgot almost
everything I knew as a child. Now, I just say a few things in the language.
9. The
book is optional. My professor said we read it if we needed extra credit. But
we read it if we don’t want to.
10. Leo:
Where is the spatula? It be in this drawer but it’s not here.
Nancy: I just did a load of dishes last night and they’re still in the dish
washer. It be in there. That’s the only other place it be.
