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Lesson 2.5: Main Verbs and Auxiliary Verbs


As we move into the syntax of verb phrases, it’s important to discover some of the differences between verbs and auxiliary verbs. There are very few auxiliary (or helping) verbs, so it’s fairly straightforward to label them, but it’s instructive to really understand some of the ways in which the two categories differ. Then one can much more easily see how auxiliary verbs and non-auxiliary verbs behave in different ways in passive constructions, in progressive and perfect aspect, in representing the future tense, and so on.


Three of the ways in which auxiliary verbs differ from “main” verbs.


1) They occur before not and can contract with it.


Lulu has not eaten lunch yet.

Lulu hasn’t eaten lunch yet.


Compare to a sentence without an auxiliary – they’re terrible (as indicated by the *)!


*Lulu eats not lunch till noon.

*Lulu eatsn’t lunch.


2) Auxiliary verbs occur in tag questions.


Bobo is running the race, isn’t he?

Bobo hasn’t finished the race yet, has he?


Try to form a tag question on a sentence without an auxiliary – yuck.


*Bobo runs the race, runsn’t he?

*Bob finished the race in second place, finishedn’t he?


3) Auxiliary verbs move to the front of the sentence in a yes/no-question. We call this Subject-Auxiliary Inversion (SAI).


Are you guys singing at the concert? (You guys are singing at the concert.)

Have you been to New York? (You have been to New York.)


Main verbs can’t do that:


*Sing you at the concert?

*Like you New York?


Another difference between main verbs and auxiliary verbs is that auxiliary verbs are a closed class: new members are never added, while we add new verbs all the time.


But it’s a better idea to let the students discover these differences for themselves.


Activity: Have students discover that auxiliary verb have and main verb have have different patterns (and meanings). Since have can be both an auxiliary and a main verb, they can compare sentences such as the following to see how tag questions and SAI behave differently in the two sets.


She hasn’t been feeling very well.

The penguins have already been fed, haven’t they?

Have your friends left for the party?


I have four dollars left.

She has an injured elbow.

We have lots of energy.


They should also come up with all of the forms of be. Everyone knows these, of course, and uses them appropriately all the time, but students sometimes don’t realize that am, is, are, was, were, being, been are all forms of be. Here’s a very brief lesson on TeachLing on this.


The auxiliary verbs are have and be.


The "dummy" auxiliary verb is do. (See more on this below.)


And the modal auxiliaries are may, might, can, could, shall, should, will, would, must). These modals are different from the auxiliaries since they do not express tense or change their forms depending on the subject. They do, however, do all of the things in (1)-(3) above.


There are related lessons on auxiliary verbs here and one on auxiliary verbs and subjects here.


Dummy Do: When there is no auxiliary and the language needs one, a form of do is stuck in. Have them figure that out.


She likes eggs. - Make it negative. What happens?

She likes eggs. - Make it a question (both by SAI and a tag). What happens?


Be - a Main Verb and Auxiliary Verb: Be is the only verb that has features of both auxiliary verbs and main verbs. It can be the only verb in a sentence (so in that way, it acts like a main verb), but also it does all of the things that auxiliary verbs do: precedes and contracts with not, moves to the front in questions, appears at the end in tag questions. It’s the last verb that can do all this, which other verbs could do in older forms of English. (“Think you a little din can daunt mine ears?” Shakespeare, The Taming of the Shrew)


Here is the lesson as a pdf.



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