Auxiliary Verbs
From TEFL World Wiki
Auxiliary (from the Latin auxilio = to help) verbs, also known as helping verbs, are verbs used to change the tense, mood and voice of other verbs.
There are three auxiliary verbs: be, have and do.
They are used before the main verb to make different tenses, negatives and questions. One or more auxiliary verbs can be used together.
Different tenses are made thus:
{auxiliary} + [auxiliary] + {main verb}
She has been waiting for three hours.
We had talked for over an hour.
The only tenses where we do not use an auxiliary verb are the present simple and the past simple.
Negative statements are made thus:
{auxiliary} + {not} + [auxiliary] + {main verb}
They have not been to Hollywood yet.
He is not living here anymore.
To make questions we use this pattern:
{auxiliary} + {subject} + [auxiliary] + {verb}
Do you want a cup of tea?
Has he been watching television?
We can also use be, have and do as lexical verbs:
I am English.
They have thirteen cats in their house.
She did it!
