Auxiliary Verbs / Helping Verbs
Most common auxiliary verbs are: To be, have, do, will.
In Progressive (Continuous) tenses:
watching TV in our room right now. (present progressive)
shopping when I saw her. (past progressive)
They have been
running for an hour. (present perfect progressive)
We had been
sleeping for an hour when the fire alarm rang. (past perfect progressive)
we always use the "-ing" form of the main verb following the auxiliary verb.
In Passive Voice
The window is
The bridge was
The new program has been
It should be
Your assignment must be
finished by tomorrow.
In Compound Tenses:
cleared all the evidence.
been done about the incident.
I don’t like horror films.
John didn’t participate our club.
Does your brother know Spanish?
Did you attend the course yesterday?
I do want to marry you.
these three auxiliary verbs (be, do and have) can also be used as full verbs, so pay attention to the words coming after them to distinguish between the two uses.
so exhausted today.
"To be" is the main verb of the sentence here as it isn't followed by a full verb.
a car and it is
Both the verb “have” (indicates possession) and “to be” are full verbs in this sentence.
Can you do
me a favor please?
I am doing
my best to pass my class.
The verb "do" is the main verb in this sentence; however, "to be" is an auxiliary verb as it is followed by the main verb (doing).
Can only be used as an auxiliary verb:
help you with the chores.
Modal Auxiliary Verbs
Most common ones are:
Can / could / may / might / shall / should / must / ought to / had better
talk to you right now.
You had better
finish your homework before your father arrives.
obey the traffic rules.
I think you should
take an aspirin.
be in his office.
you open the door for me, please?
See Auxiliary Verbs Exercise