1. What are auxiliary verbs?
Grammar Toolkit
Auxiliary verbs
What are auxiliary verbs?

2. Grammar Toolkit
Auxiliary verbs
A non-finite verb can become a finite verb with the help of an auxiliary or “helping” verb. Auxiliary verbs give the resulting verb its tense. Let’s start with the present participle looking.
The auxiliary verb is makes the verb complete and gives it a tense (present tense.)
Mickey is
looking
The complete verb can now have a subject.
By itself, it doesn’t have a tense and can’t have a subject.
The complete finite verb becomes is looking.

3. have has do does did be am is are was were being been
Grammar Toolkit
Auxiliary verbs
Auxiliary verbs are forms of the verbs have, do and be. Choose an auxiliary verb for each non-finite verb. What tense does the complete verb get?
have has do does did be am is are was were being been
I ______ cleaning.
She _______sure.
We to go.
Yuki and Sanj coming.
I know. am
present
was
past
have
present
are
present
did
past

4. can could may might must shall should will would
Grammar Toolkit
Auxiliary verbs
Modal verbs are a type of auxiliary verb. They help a non-finite verb express possibility, obligation or permission. Choose an auxiliary verb for each non-finite verb. What tense does the complete verb get?
can could may might must shall should will would
we dance?
You eat.
Mia run fast.
Jack go.
They know.
Shall
future
must
present
can
present
will
future
might
present

5. A main verb plus one or more auxiliary verbs makes a verb phrase.
Grammar Toolkit
Auxiliary verbs
A main verb plus one or more auxiliary verbs makes a verb phrase.
may
have
been
played
Verb phrases can become quite long. What verb phrases can you make with these auxiliary verbs?
been is will was have had
Carlos playing.
Carlos playing.
Carlos playing. is
was
had been
will have been

6. Many negative verb phrases are also written as contractions.
Grammar Toolkit
Auxiliary verbs
Many subjects and their auxiliary verbs are written as contractions. Contractions are words or phrases with an apostrophe to show missing letters.
I’m home. = I am home. Cristina’s here. = Cristina is here.
Many negative verb phrases are also written as contractions.
She hasn’t sold it. = She has not sold it. He didn’t arrive. = He did not arrive.

7. subject + auxiliary verb
Grammar Toolkit
Auxiliary verbs
Do you know what these contractions mean?
subject + auxiliary verb
contraction
I have
you are
I had
it’s
they’re
I’ve
you’re
I’d
it is
they are
contraction
negative verb phrase
can’t
don’t
shouldn’t
will not
had not
cannot
do not
should not
won’t
hadn’t

8. Verbs have different forms.
Grammar Toolkit
Auxiliary verbs
Verbs have different forms.
A finite verb is a verb with a subject and tense. A non-finite verb doesn’t have a subject or tense and cannot be the main verb in a sentence.
Non-finite verbs can become finite verbs with the help of auxiliary verbs (forms of the verbs have, do and be), including modal verbs.
Adding one or more auxiliary verbs to a main verb forms a verb phrase.
Many subjects and their auxiliary verbs are written as contractions (e.g. she’d = she had), as are negative verb phrases (e.g. don’t = do not).

9. Grammar Toolkit
Auxiliary verbs
The End