Helping(Auxiliary) Verbs

HELPING AND
MODAL AUXILIARY
VERBS

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.
(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 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.
a. To add emphasis to an entire sentence: "He does like spinach. He really does!"
b. To add emphasis to an imperative: "Do come in." (actually softens the command)
c. To add emphasis to a frequency adverb: "He never did understand his father." "She always does manage to hurt her mother's feelings."
d. To contradict a negative statement: "You didn't do your homework, did you?" "Oh, but I did finish it."
e. To ask a clarifying question about a previous negative statement: "Ridwell didn't take the tools." "Then who did take the tools?"
f. 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.
Based on descriptions in Grammar Dimensions: Form, Meaning, and Use 2nd Ed. by Jan Frodesen and Janet Eyring. Heinle & Heinle: Boston. 1997. Examples our own.

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 Active Voice 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.
Based on the analysis in Grammar Dimensions: Form, Meaning, and Use 2nd Ed. by Jan Frodesen and Janet Eyring. Heinle & Heinle: Boston. 1997. Examples our own.