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Auxiliary Verbs or Helping

Auxiliary Verbs or Helping

Helping verbs or auxiliary verbssuchas will, shall, may, might, can, could, must, ought to, should, would, used to, needare used in conjunction with main verbsto express shades of timeand mood. The combination of helping verbs with main verbs creates whatare called verb phrases or verb strings. In the following sentence, "will have been"are helping orauxiliary verbsand "studying"is the main verb; the whole verb stringis underlined:
  • As of nextAugust, I will have been studyingchemistry for ten years.

Students should remember thatadverbsand contracted formsare not, technically, part of the verb. In the sentence, "He hasalready started." theadverb alreadymodifies the verb, but itis not really part of the verb. The sameis true of the 'ntin "He hasn't started yet" (theadverb not, represented by the contracted n't,is not part of the verb, has started).
Shall, willand forms of have, doand becombine with main verbs to indicate timeand voice.Asauxiliaries, the verbs be, have and docan change form to indicate changes in subjectand time.

  • I shall go now.
  • He had won the election.
  • They didwrite that novel together.
  • I am going now.
  • He was winning the election.
  • They have beenwriting that novel fora long time.

Uses of Shall and Willand Should

In England, shallis used to express the simple future for first person Iand we,as in "Shall we meet by the river?" Willwould be used in the simple future forall other persons. Using willin the first person would express determination on the part of the speaker,as in "We will finish this project by tonight, by golly!" Using shallin secondand third persons would indicate some kind of promiseabout the subject,as in "This shall be revealed to you in good time." This usageis certainlyacceptable in the U.S.,although shallis used far less frequently. The distinction between the twois often obscured by the contraction 'll,whichis the same for both verbs.
In the United States, we seldom use shallforanything other than polite questions (suggestingan element of permission) in the first-person:
  • "Shall we go now?"
  • "Shall I calla doctor for you?"
(In the second sentence, many writers would use shouldinstead,although shouldis somewhat more tentative than shall.) In the U.S., to express the future tense, the verb willis used inall other cases.
Shallis often used in formal situations (legal or legalistic documents, minutes to meetings, etc.) to express obligation, even with third-personand 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."
Shouldis usually replaced, nowadays, by would. Itis still used, however, to mean "ought to"as in
  • You really shouldn't do that.
  • If you think that wasamazing, you should have seen it last night.
In British Englishand very formalAmerican English, oneisapt to hear or read shouldwith the first-person pronouns in expressions of liking suchas "I should prefer iced tea" and in tentative expressions of opinion suchas
  • I should imagine they'll vote Conservative.
  • I should have thought so.
(The New Fowler's Modern English Usageedited by R.W. Burchfield. Clarendon Press: Oxford, England. 1996. Used with the permission of Oxford University Press. Examples our own.)

Uses of Do, Doesand Did

In the simple present tense, dowill functionasanauxiliary to express the negativeand toask questions. (Does, however,is substituted for third-person, singular subjects in the present tense. The past tense didworks withall persons, singular and plural.)
  • I don't studyat night.
  • She doesn't work hereanymore.
  • Do youattend this school?
  • Does he work here?
These verbsalso workas "shortanswers," with the main verb omitted.
  • Does she work here? No, she doesn't work here.
With "yes-no" questions, the form of dogoes in front of the subjectand the main verb comesafter the subject:
  • Didyour grandmother knowTruman?
  • Do wildflowers growin your back yard?
Forms of doare useful in expressing similarityand differences in conjunction with soand neither.
  • My wife hates spinach and so does my son.
  • My wife doesn't like spinach; neither do I.
Doisalso helpful because it means you don't have to repeat the verb:
  • Larry excelled in language studies; so didhis brother.
  • Raoul studiesas hardas his sister does.
The so-called emphatic dohas many uses in English.
  1. Toadd emphasis toan entire sentence: "He doeslike spinach. He really does!"
  2. Toadd emphasis toan imperative: "Docome in." (actually softens the command)
  3. Toadd emphasis toa frequencyadverb: "He never didunderstand his father." "Shealways doesmanage to hurt her mother's feelings."
  4. To contradicta negative statement: "You didn't do your homework, did you?" "Oh, but I didfinish it."
  5. Toaska clarifying questionabouta previous negative statement: "Ridwell didn't take the tools." "Then who didtake the tools?"
  6. To indicatea strong concession: "Although the Clintons deniedany wrong-doing, they did return some of the gifts."
In theabsence of other modalauxiliaries,a form of dois used in questionand negative constructions knownas the get passive:
  • DidRinaldo get selected by the committee?
  • Theaudience didn't get riled up by the politician.
Based on descriptions in Grammar Dimensions: Form, Meaning,and Use2nd Ed. by Jan Frodesenand Janet Eyring. Heinle & Heinle: Boston. 1997. Examples our own.

Uses of Have, Has and Had

Forms of the verb to haveare used to create tenses knownas the present perfectand past perfect. The perfect tenses indicate that something has happened in the past; the present perfect indicating that something happenedand might be continuing to happen, the past perfect indicating that something happened prior to something else happening. (That sounds worse than it reallyis!) See the section on Verb Tenses in theActive Voicefor further explanation;also review material in the Directory of English Tenses.
To have isalso in combination with other modal verbs to express probabilityand possibility in the past.
  • Asanaffirmative statement, to havecan express how certain youare that something happened (when combined withanappropriate modal + have+a past participle): "Georgia must have leftalready." "Clinton might have knownabout the gifts." "They may have votedalready."
  • Asa negative statement,a modalis combined with not + have+a past participle to express how certain youare that something did not happen: "Clinton might not have knownabout the gifts." "I may not have been thereat the time of the crime."
  • Toaskabout possibility or probability in the past,a modalis combined with the subject + have+ past participle: "Could Clinton have knownabout the gifts?"
  • For shortanswers,a modalis combined with have: "Did Clinton knowabout this?" "I don't know. He may have." "The evidenceis pretty positive. He must have."
To have (sometimes combined with to get)is used to expressa logical inference:
  • It's been rainingall 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!
Haveis often combined withan infinitive to formanauxiliary whose meaningis similar to "must."
  • I have to havea car like that!
  • She has to pay her own tuitionat college.
  • He has to have been the first student to try that.
    Based on theanalysis in Grammar Dimensions: Form, Meaning,and Use2nd Ed. by Jan Frodesenand Janet Eyring. Heinle & Heinle: Boston. 1997. Examples our own.




    Other helping verbs, called modalauxiliaries or modals, suchas can, could, may, might, must, ought to, shall, should, will,and would, do not change form for different subjects. For instance, try substitutingany of these modalauxiliaries for canwithany of the subjects listed below.

    you (singular)
    you (plural)
    can write well.

    Thereisalsoa separate section on the ModalAuxiliaries, which divides these verbs into their various meanings of necessity,advice,ability, expectation, permission, possibility, etc.,and provides sample sentences in various tenses. See the section on Conditional Verb Formsfor help with the modalauxiliary would. The shades of meaningamong modalauxiliariesare multifariousand complex. Most English-as-a-Second-Language textbooks will containat least one chapter on their usage. For moreadvanced students, A University Grammar of English, by Randolph Quirkand Sidney Greenbaum, containsan excellent, extensiveanalysis of modalauxiliaries.
    Theanalysis of ModalAuxiliariesis based ona similaranalysis in The Scott, Foresman Handbook for Writersby Maxine Hairstonand John J. Ruszkiewicz. 4th ed. HarperCollins: New York. 1996. The description of helping verbs on this pageis based on The Little, Brown Handbookby H. Ramsay Fowlerand Jane E.Aaron, & Kay Limburg. 6th ed. HarperCollins: New York. 1995. By permission ofAddison-Wesley Educational Publishers Inc. Examples inall casesare our own.

    Uses of Can and Could

    The modalauxiliary canis used
    • to expressability (in the sense of beingable 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 beingallowed or permitted to do something):
      Can I talk to my friends in the library waiting room? (Note that canis less formal than may.Also, some writers will object to the use of canin this context.)
    • to express theoretical possibility:
      Americanautomobile makers can make better cars if they think there'sa profit in it.
    The modalauxiliary couldis used
    • to expressanability in the past:
      I couldalways beat youat 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 couldalways spend theafternoon just sittingaround talking.
    • to express possibility orability in contingent circumstances:
      If he studied harder, he could pass this course.
    In expressingability, can and couldfrequentlyalso imply willingness: Can you help me with my homework?

    Can versus May

    Whether theauxiliary verb cancan 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 whoisattentive to the proprieties will preserve the traditional distinction: canforability or power to do something, mayfor permission to do it.
    The questionisat what level can you safely ignore the "proprieties." Merriam-Webster's Dictionary, tenth edition, says the battleis overand can can be used in virtuallyany situation to express orask for permission. Mostauthorities, however, recommenda stricteradherence 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 modalauxiliariesare may and might. When used in the context of granting or seeking permission, mightis the past tense of may. Mightis considerably more tentative than may.
    • May I leave class early?
    • If I've finishedall my workand I'm really quiet, might I leave early?
    In the context of expressing possibility, may and mightare interchangeable presentand future formsand might + have+ past participleis the past form:
    • She might be myadvisor next semester.
    • She may be myadvisor next semester.
    • She might haveadvised me not to take biology.
    Avoid confusing the sense of possibility in maywith the implication of might,thata hypothetical situation has not in fact occurred. For instance, let's say there's beena helicopter crashat theairport. In his initial report, beforeall the factsare gathered,a newscaster could say that the pilot "mayhave been injured."After we discover that the pilotis in factall right, the newscaster can now say that the pilot "mighthave been injured" because itisa hypothetical situation that has not occurred.Another example:a body had been identifiedafter much work bya detective. It was reported that "without this painstaking work, the body mayhave remained unidentified." Since the body was, in fact, identified, mightis clearly called for.

    Uses of Willand Would

    In certain contexts, willand wouldare virtually interchangeable, but thereare differences. Notice that the contracted form 'llis very frequently used for will.
    Willcan be used to express willingness:
    • I'll wash the dishes if you dry.
    • We're going to the movies. Will you join us?
    It canalso 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.
    Wouldcanalso be used to express willingness:
    • Would you please take off your hat?
    It canalso express insistence (rather rare,and witha strong stress on the word "would"):
    • Now you've ruined everything. You wouldact that way.
    and characteristicactivity:
    • 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.
    Ina main clause, wouldcan expressa hypothetical meaning:
    • My cocker spaniel would weigha ton if I let her eat what she wants.
    Finally, wouldcan expressa sense of probability:
    • I heara whistle. That would be the five o'clock train.

    Uses of Used to

    Theauxiliary verb construction used tois used to expressanaction that took place in the past, perhaps customarily, but now thataction no longer customarily takes place:
    • We used to take long vacation trips with the whole family.
    The spelling of this verbisa 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. Thereare exceptions, though. When theauxiliaryis combined withanotherauxiliary, did,the past tenseis carried by the newauxiliary and the "-ed" endingis 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 tocanalso be used to convey the sense of beingaccustomed 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 tois best reserved for colloquial usage; it has no place in formal oracademic text.

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