Uses Of Auxiliary Verbs and Uses Of Modal Verbs

How to Use Auxiliaries and Modals
Be

The auxiliary be is used

(1)    In the formation of the continuous tenses ; as,

He is sleeping. I was working.

(2)    In the formation of the passive ; as,

The thief was punished.

Be  followed by the infinitive is used

(1)    To indicate a plan, arrangement, or agreement ; as,

·         I am to meet her tomorrow.

·         They are to be married next month.

(2)    To denote command ; as,

·         You are to write your roll number at the top of each sheet of paper.

·         Father says you are to go to market immediately.

Be is used in the past tense with the perfect infinitive to indicate an arrangement that was made but not carried out ; as,

                We were to have been married last month but had to postpone the marriage until July.

Have

The auxiliary have is used in the formation of the perfect tenses ; as

·         She has sung. She has been singing.

Have to is used with the infinitive to indicate obligation ; as

·         We have to be there by five o’clock.

·         She had to move the furniture herself.

In negative and questions, have to and  had to are used with do, does, did; as,

·         I have to go -> I don’t have to go. Do they have to go?

·         She has  to go -> She doesn’t have to go. Does she have to go ?

·         We had to go -> We didn’t have to go. Did we have to go ?

Do

The auxiliary do is used

(1)    To form the negative and interrogative of the simple present and simple past tenses of ordinary verbs ; as,

·         She does n’t work.

·         She did not work.

·         Does she work ?

·         Did she work ?

(2)    To avoid repetition of the verb ; as,

·         Do you know her ? Yes, I do.

·         He sings well. Yes, he does.

·         You met him, didn’t you ?

·         He eats fish and so do I.

-          Do is also used to emphasize the affirmative nature of a statement ; as,

·         You do look pale.

·         She told me not to go, but I did go.

-          In the imperative, do makes a request or invitation more persuasive ; as,

·         Do be quiet.

·         Oh, do come ! It’s going to be such fun.

In such cases do is strongly stressed.

Can, Could, May, Might

 Can usually expresses ability or capacity ; as,

·         She can swim across the river.

·         I can work this sum.

·         Can you lift this heavy box?

Can and May are used to express permission. May is rather formal.

·         You can/may go now.

·         Can/May I borrow your scooter ?

May is used to express possibility in affirmative sentences. Can is used in the corresponding interrogative sentences.

·         It may rain tomarrow.

·         She may be at home.

·         Can this be true ?

·         I can not be true.

Compare – ‘It cannot be true’ with, ‘It may be true’. Cannot denotes imposibility, while may not denotes improbability.

In very formal English, may is used to express a wish as,

·         May you live happily and long !

·         May success attend you !

Could and Might are used as the past equivalent of can and may ; as,

·         She could swim across the river when she was young . (Ability)

·         She said I might/could go. (Permission)

·         He wondered whether is could be true. (Possibility)

Could, as in the first example above, expresses only ability to do an act, but not the performance of an act. We should use was/were able to for ability + action in the past.

                When the boat was upset, they were able to (or managed to ) swim to the bank, (not : we could swim to the bank).

In negative statements, however, either could or  was/were able to may be used.

She couldn’t (or : wasn’t able to) solve the puzzel. It was too difficult.

Might is also used to express a degree of dissatisfaction or reproach ; as

                She might pay a little more attention to her beauty.

# Note the use of can, could, may and might with the perfect infinitive.

·         She is not there. Where can she have gone ? (= Where is it possible that she has gone ? May express annoyence.)

·         You could have accepted the offer. (= Why didn’t you accept the offer ?)

·         Rohini may/might have gone with Sunita. (=Possibly Rohini has gone/went with Sunita)

·         Why did you drive so carelessly ? You might have run into the lamppost. (= It is fortunate that you didn’t run into the lamppost.)

Shall, Should, Will, Would

Shall is used in the first person and will in all persons to express pure future. Today I/we shall is less common then I/we will.

·         I shall/will be twenty-five next birthday.

·         We will need the money on 26^th.

·         Where shall we see you again ?

·         Tomorrow will be Friday.

·         You will see that I am right.

In present-day English, However, there is a growing tendency to use will in all persons.

Shall is sometimes used in the second and third persons to express a command, a promise, or threat; as,

8 He shall not enter my room again. (Command)

You shall have a holiday tomorrow. (Promise)

You shall be punished for this. (Threat)

                Note that these uses of shall are old-fashioned and formal and generally avoided in modern English.

Shall is used in the second and third persons to ask after the will of the person addressed; as,

·         Shall I open the window ? (i.e. Do you wish me to open it ?)

·         Which pen shall I buy ? (i.e. What is your suggestion ?)

·         Shall the waiter serve coffee now ?

Will is used to express:

(1)    Volition ; as,

·         I will (= am willing to) carry your books.

·         I will (= promise to ) try to do better next time.

·         I will (= am determined to ) succeed or die in the attempt.

(2)    Characteristic habit ; as,

·         She will about nothing but games.

·         He will sit for hours listening to the radio.

(3)    Assumption or probability ; as,

·         This will be the pot you want, I suppose.

·         That will be the plumber, I think.

Will you ? indicates an invitation or request ; as,

·         Will you have tea ?

·         Will you lend me your scooter ?

Should  and would are used as the past equivalents of shall and will ; as,

·         I expected that I would get a first class.

·         He said he would be twenty-five next birthday.

·         He said she would carry my books.

·         She would sit for hours listening to the wireless. (Past habit)

Should is used in all persons to express duty or obligation ; as,

·         We should obey the laws.

·         You should keep your promise.

·         Children should obey their parents.

Should and would are used as in the examples below.

(i)                  I should (or : would) like you to help her. (‘should/would like’ is a polite form of ‘want’)

(ii)                Would you lend me your scooter. Please ? (‘would you ?’ is more polite then ‘will you?’)

(iii)               You should have been more careful. (Should + perfect infinitive indicates a past obligation that was not fulfilled)

(iv)              He should be in the library now. (Expresses probability)

(v)                I wish you would not chatter so much. (Would after wish expresses a strong desire.)

Must, Ought to

Must is used to express necessity or obligation.

·         You must improve your spelling hand writing.

·         We must get up early in the morning.

Must refers to the present or the near future. To talk about the past. We use had to (the past form of have to ); must has no past form.

·         Yesterday we had to get up early in the morning.

Must is often used when the obligation comes from the speaker. When the obligation comes from somewhere else, have to is often used. Compare :

·         I must be on a diet. (It is my own idea.)

·         I have to be on a diet. (The doctor has told me to be on a diet.)

Must can also express ligical certainly.

·         Living in such crowded conditions must be difficult. (= I am sure it is difficult.)

·         She must have left already. (I am sure she has left already.)

Ought (to) express moral obligation or desirability ; as,

·         We ought to love our neighbours as much as we love ourselves.

·         You ought to help him with money.

·         She ought to know better.

Ought (to) can also be used to express probability.

·         Prices ought to come down soon.

·         This book ought to be very useful.