Auxiliary Verbs in English
An auxiliary verb is a word that helps a main verb indicate when the action of a sentence takes place. The times an action can take place are expressed with the following tenses:
An auxiliary verb plus a main verb is called a compound tense (or sometimes a verb phrase). English has several auxiliary verbs such as “to be", “to do", “to have", “will", “may", “might", and others. These words either help the verb express the time of an action or change the meaning of the main verb. Auxiliary verbs serve many functions but the most common include:
(1) Indicating the tense of the main verb, as in:
John is watching television.
(2) Forming the Perfect system of tenses, as in:
Sue had seen the movie.
(3) Indicating a passive voice verb, as in:
John was given an award.
(4) Indicating the subjunctive mood, as in:
Sarah may go to the store.