Auxiliary Verbs & Modals

Primary Auxiliary Verbs

be

do

have

Functions of Auxiliaries

Modal Auxiliary Verbs

(be) able to, can, could

may, might

should, must, ought to

used to, would

Will & Shall

More Modals

Modals Tests 1, 2, 3

to Verbs to Learning English

 

Auxiliary Verbs

Auxiliary verbs are of two types:  Primary and Modal.  These verbs are used with other verbs to form some of the various tenses.    Some auxiliaries may be used alone:  

The primary auxiliaries and their forms are:

(To list all the uses and the definitions would be too lengthy.  Check a dictionary for more options.)

BE

Important note: The first person singular---I--requires the contraction aren't  for a negative question. There is no English word for am not.  .For the negative statement, use I'm not, as shown in the chart that follows.

Primary Aux. Verb Positive Negative Contraction
Present (1st person singular) AM (I'm) AM NOT, (I'm not) AREN'T
Present (3rd person singular) IS (he's, she's)* IS NOT, (he's not, she's not) ISN'T
Present (2nd singular, 1 & 3 plural) ARE (you're) ARE NOT, (you're not) AREN'T
Past (1 & 3 singular) WAS WAS NOT WASN'T
Past (2 singular, 1 & 3 plural) WERE (we're, they're) WERE NOT WEREN'T
-ing form BEING NOT BEING  

-ed participle

BEEN    

be (to exist:  I am tired) (a continuing action:   We are working.) 

*Note that he's & she's can mean he is (she is) AND he has (she has).  The context of the sentence should let you know which form is being used.

DO

Primary Aux. Verb Positive Negative Contraction
Present (first & second person) DO DO NOT DON'T
Present (third person) DOES DOES NOT DOESN'T
Past DID DID NOT DIDN'T

 

 

When do (to perform, to fulfill, to create; to complete:  I did that already) is used as a main verb, it also has the form doing for the present participle  and done for the past participle. 

HAVE

Primary Aux. Verb Positive Negative Contraction
Present (first & second person) HAVE (I've, you've) HAVE NOT,  (I've not, you've not) HAVEN'T
Present (third person) HAS  (he's, she's)* HAS NOT, (he's not, she's not) HASN'T
Past HAD (I'd, you'd, he'd, she'd, we'd) HAD NOT,  (I'd not, you'd not, etc) HADN'T
-ing form HAVING NOT HAVING  
-ed participle HAD    

have (to possess:   I have a cold)  (completed in the past; I had done the work.   I have done the work.)

*Note that he's & she's can mean he is (she is) AND he has (she has).  The context of the sentence should let you know which form is being used.

All auxiliaries perform these six functions:

  1. Followed immediately by not, they make a sentence negative.  "I have not finished speaking yet."

  2. Followed by the subject, then by the rest of the verbal phrase, they form an interrogative sentence (a question).  "Did you answer the phone?"  

  3. Using the n't contraction form followed by the subject , then the rest of the verb creates a negative question.  "Didn't you answer the phone?"

  4. They supply the verbal past of tag questions( a tag question is the auxiliary with a pronoun).  "You've eaten supper, haven't you?"  "You haven't eaten supper, have you?"

  5. They supply an emphatic affirmative.  "Did you get the report done?  Yes, I have finished."

  6. They act as a substitute for the entire predicate.  Sheldon hasn't taken his shower, but I have.

    ("taken my shower is omitted, because it's assumed.)  She has studied, but I haven't.  

Now try some sentences of your own using each of the auxiliaries.

 

Modal Auxiliary Verbs

Modals are auxiliary verbs that add to the meaning of the main verb by suggesting possibility, necessity, permission, obligation, prohibition, or ability.  That is why they have so many shades of meaning in a sentence.  Some common modals in English are: (be) able to, can, could, may, might, will, would, shall, should, must, ought to.

 

Positive

Meaning

Negative & Contraction
(BE) ABLE TO ability 

She is able to dance.

NOT ABLE

CAN expresses ability

I can do anything you can!

asking or giving permission (informal usage)

Can I have a new car Dad?

offer

Can I do anything for you?

request, instruction

Can you show me how to work this?  (Do you know how . . .)

capability

Barney can be a real tiger on the tennis court.

comment...observation of capability

Sarah can be very persistent at times.

CAN NOT, CANNOT, CAN'T

I can't do this lesson!

 

No you can't.

 

Can't I do anything for you?

when something seems  impossible

Paul can't be that old!  (I can't believe he is 97.)

 

 

 

 

COULD ability in the past

Jim could do the hokey pokey when he was ten years old.

possibility or uncertainty  

Could Korea win the next World Cup?

request (more polite than can, but still informal usage)

Could you please turn down the radio?

suggestion

They could go to the skating rink tomorrow.

asking or giving permission

Could I borrow five dollars?

with comparative adjectives to show possibility or impossibility 

Shelly could swim better than David.

COULD NOT, COULDN'T

We couldn't get to the airport on time.

 

Couldn't Korea win the next World Cup? (Isn't it possible that Korea...?)

 

 

 

 

 

 

 

unwillingness/inability

Angela couldn't scold the dog when he looked so pitiful. 

Jon couldn't sing as well as Jana.

MAY requests permission

May I take you to lunch today?

indicates possibility

It may rain today, or it may not.

*MAY NOT (denying permission)

You may not borrow my cellular 'phone.

*MAY NOT (negative possibility)

They said they were going to the fair, but with the rain, they may not (go).

MIGHT indicates possibility or uncertainty

I might go tomorrow, if the weather is nice.

unreal or unlikely situation

If I win the lottery, I might buy a yacht.

MIGHT NOT, MIGHTN'T

Perry might not like your wearing his new shirt.

 

SHOULD

obligation, duty, necessity

She should clean the house today.

expectation

The concert tonight should be fantastic.

advice, opinion

Alma should take a nap before trying to teach six hours non-stop.

something wrong or unexpected

She said he should wash the dog, not watch the dog!

SHOULD NOT, SHOULDN'T

(direct order or strong advice)

 

 

 

 

 

 

You should not do any hard physical work after having surgery.

 

MUST something that's mandatory... obligation

Duane must practice the guitar more.

when you are sure of a truth 

Carl must be home by now.  (I’m sure he is home).

necessity

I must fill the gas tank before starting the trip.

order, strong suggestion

Marcia, you  must pick up some groceries or you will get no supper.

MUST NOT, MUSTN'T

prohibited/forbidden

You must not chew with your mouth open.

We mustn't drive on that street, because it's closed for repair.

 

OUGHT TO obligation or duty

Everyone ought to obey traffic laws.

expectation 

Betty likes Elton John, so she ought to love this new CD.

recommendation

We ought to read the instructions before we try to assemble bookcase.

OUGHT NOT TO**, OUGHTN'T TO

criticism 

Susanne ought not to hide the dirty dishes in the oven when her mother-in-law visits.

 

They oughtn't to have lied to him.

 

USED TO/USE TO

When combined with 'did', 'used to' becomes 'use to'.  "Did" shows the past tense instead.

 

something that customarily took place in the past, but no longer takes place

They used to go camping every summer.

Accustomed to or familiar with something

Don't change now.  I am used to you as you are.

USED NOT TO/DIDN'T USE TO

He didn't use to jog, but he does it every day now.

NOT USED TO----not adjusted to, or not adapted to

I'm not used to the new work hours

WOULD

 

 

WOULD LIKE

request 

Marcus, would you get me a glass of water? 

offer/invitation

Would you like some tea?

after be, followed by adjectives doubtful, unlikely--a tentative action

 It's unlikely that he would be on time for anything.

annoying habit, typical behaviour

Peter would ask a hard question, wouldn't he? 

WOULD NOT, WOULDN'T

certainty (an implied conditional sentence

Whitney wouldn't say that. (I know Whitney's personality, and she's not capable of saying that.)

 

 

* Mayn't is never used in American English.  ** Shan't is rarely used in American English conversation, but you will find it in literature.  ***American English occasionally uses ought and its forms without the to in negative sentences and questions.

Should is used more commonly in these types of sentences however.

Modal Tests  1 & 2 & 3

Will and Shall  

Will and shall are modal auxiliary verbs.  They do not change their form except when they are contractions and they followed by the main verb.   There are several rules as to when to use which of these verbs, but in American English will is used much more than shall.  Shall is used in the question form as stated below and in certain expressions.  Many times, shall in a question form  means Is it a good idea to...? It is used when asking someone's opinion, or inquiring about their wishes.  Formal American English uses shall to indicate an explicit obligation  (Passengers shall show their boarding passes at the gate.) 

Shall is usually only used in the first person (I or we) and is used in questions.

Will is NOT usually used in first person questions.  (Will is also used as a contraction as in I’ll do it= I will do it.  It'll be dark at that time = It will be dark...)        

Noun or Pronoun Sentence Question
Jack Jack will visit tomorrow Will Jack visit tomorrow?
I I will visit tomorrow.  (I’ll) Shall I visit tomorrow?
We We will visit tomorrow.  (We’ll) Shall we visit tomorrow?
You You will visit tomorrow.  (You’ll) Will you visit tomorrow?
He He will visit tomorrow.  (He’ll) Will he visit tomorrow?
She She will visit tomorrow.  (She’ll) Will she visit tomorrow?
It It will be nice to have visitors tomorrow.  (It’ll) Will it be nice to have visitors tomorrow?
They They will visit tomorrow.  (They’ll) Will they visit tomorrow?

Will can be used with a first person subject (I, we) and shall can be used with a second or third person subject (you, he, she, it, they) to show determination or promise or obligation, depending on the context.  

  (To show a negative use:  shall not, shan’t; will not, won’t.)

   Since will and shall can be so tricky, and since American English at least uses shall so seldom (except in the question form), you will be correct and safe in using will for most of your sentences.

Other situations in which to use will

 won’t  

Some other modals

 

don’t have to, don’t need to:  When you aren’t obligated to do something .

had better:  Giving strong advice (almost a mild threat in some cases)  

have (got) to:  This shows a necessity, not a personal one, but for a situation.  (usually have to is better to use than must)  

may as well/might as well:  These modals describe the only thing possible option, even if it isn’t a desired choice  

need to:  This means a requirement or necessity.  

needn’t (need not):  It isn't necessary to do something.  

 

Tenses and modals quiz

 Re-write the sentences using the correct verb form of the words in red adding any auxiliary verbs and modals that may be needed.  Only the words in red may be changed, although you may use contractions.  Remember your tenses!

 

Ozzie should wash before he went to the concert.                                 have washed

Betty will take belly dancing lessons for two years by January.                      have been taking

They would not allow us to hold the protest if we hadn’t had a permit.                   have allowed

Thomas should study more, then he would have passed his college exams.                       have studied.

She had a perfect wedding, so she must do months of planning.                   have done

If you didn’t want to go to the museum, you should say something.                        have said

You should not go swimming if you felt ill.                                                       have gone

Aunt Tilly didn’t need make so much food for the picnic, but she did.                     to make

He must be exercise for several months because he has lost a lot of weight.                        have been exercising

Will the Browns be visit the seashore this year?                                                            visiting

Paul doesn’t have talk in class, but his teacher prefers that he does.              to talk

Rhonda may as well leave the movie early—nothing exciting happened at the end.         have left

William could have relax by now, if he had finished his work.                      been relaxing

I had forget where my keys were, but Mike remembered.                               forgotten

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