SUBSTITUTION DRILL: Auxiliary Verbs (Have/do/can, etc.)
I think so/ I hope so, etc.
The most common auxiliary verbs are "be," "do," and "have", and you may also
use these verbs on their own. You use "Will" and "shall" to express future time.

In each of the following examples, a verb commonly used as an auxiliary verb
appears as a simple predicate:

She is the chief engineer.
The tea cups are in the china cabinet.
Garth does this kind of thing frequently.
My roommates and I do the laundry every second week.
I can't complete my assignment because he still has my notes.
They have several kinds of gelato in the display case.
Other common auxiliaries are "can," "could," "may," "might," "must," "ought,"
"should," "will," and "would." A verb like these is called a modal auxiliary and
expresses necessity, obligation, or possibility.

The highlighted word in each of the following sentences is a modal auxiliary:

Zora was pleased to learn that she could take several days off.
The small freckled girl told her neighbors that she would walk their dog for
an appropriate fee.
Henry told Eliza that she ought to have the hole in the bucket fixed.
The principal told the assembled students that the school board might introduce
a dress code next autumn.
According to the instructions, we must leave this goo in our hair for twenty minutes.
Several words may intervene between the auxiliary and the verb which goes
with it, as in the following sentences:

They have not delivered the documents on time.
The treasure chest was never discovered.
The health department has recently decided that all high school students should
be immunised against meningitis.
Will you walk the dog tonight?
The ballet corps was rapidly and gracefully pirouetting about the stage.



There are two verbs in each of these sentences:

I                     Have               Lost                my keys.
She                Can’t               come              to the party.
The hotel         was                built                ten years ago.
Where             do you             live?

Ø You can use an auxiliary verb when we don’t want to repeat something.
Ø Use do/does/did for simple present and past:
Ø We use you have? She isn’t? they do? Etc. to show polite interest in what
   somebody has said.
Ø Sometimes we used inverted word order (Have you?/ Isn’t she?) to show
   surprise


Examples:

1. Have you locked the door?
2. Do you like onions?
3. Does Mike play soccer?
4. Sue doesn’t have a car, and neither does Mark.
5. I passed the exam and so did Tom.