Traditional grammars define verbs as words that “describe an action or a state.” Auxiliary verbs are a subclass of verbs that add functional or grammatical meaning to the main verb. Auxiliary verbs differ from prototypical verbs in that auxiliary verbs perform a limited set of grammatical functions.
In grammar, a progressive is a word that expresses the progressive aspect in the English language. The auxiliary verb that can function as the progressive is the verb be, which is referred to as the progressive be. Do not confuse the progressive be with the copular be or passive be. For example, the following italicized auxiliary verbs function as progressives:
- I am bowling a perfect game.
- You are stealing a priceless heirloom.
- She is drinking sweet tea.
- He was reciting poetry on the quad.
- We were watching our favorite show when the cable went out.
- My puppy had been gnawing on the rawhide bone.
Brinton, Laurel J. & Donna M. Brinton. 2010. The linguistic structure of Modern English, 2nd edn. Amsterdam: John Benjamins Publishing Company.
Hopper, Paul J. 1999. A short course in grammar. New York: W. W. Norton & Company.
Huddleston, Rodney. 1984. Introduction to the grammar of English. Cambridge: Cambridge University Press.
Kilby, David. 1984. Descriptive syntax and the English verb. Dover, New Hampshire: Croom Helm.
Leech, Geoffrey N. 2004. Meaning and the English verb. Harlow, English: Pearson Longman.