VERBOS AUXILIARES

AUXILIARY VERBS

Auxiliary Verbs are the verbs be, do, have, will when they are followed by another verb (the full verb) in order to form a question, a negative sentence, a compound tense or the passive.

The verb "be"

The verb be can be used as an auxiliary and a full verb. As an auxiliary we use this verb for compound tenses and the passive voice. Note that be is an irregular verb:

Simple Present:

I am, he/she/it is, we/you/they are

Simple Past:

I/he/she/it was, we/you/they were

Past Participle:

been

The verb "have"

The verb have, too, can be used both as an auxiliary and as a full verb. As an auxiliary we use this verb to form compound tenses in active and passive voice. (Use the past participle of the full verb.)
Compound Tenses - Active Voice

Present Perfect Simple:

He has played football.

Past Perfect Simple:

He had played football.

Present Perfect Progressive:

He has been playing football.

Past Perfect Progressive:

He had been playing football.

The verb "will"

The verb will can only be used as an auxiliary. We use it to form the future tenses.
The auxiliary verb "will"

Future I:

He will not play football.

Future II:

He will have played football.

The verb will remains the same for all forms (no "s" for 3rd person singular). The short form for negative sentences is won't.'

Examples:

I will, he will

I will not = I won't

The verb "do"

The verb do can be both an auxiliary and a full verb. As an auxiliary we use do in negative sentences and questions for most verbs (except not for be, will, have got and modal verbs) in Simple Present and Simple Past. (Use the infinitive of the full verb.)
The auxiliary "do" in negative sentences

Simple Present:

He does not play football.

Simple Past:

He did not play football.

The auxiliary "do" in questions

Simple Present:

Does he play football?

Simple Past:

Did he play football?

 

Now there are some exercises to check your brain:

http://www.ego4u.com/en/cram-up/grammar/auxiliary-verbs/exercises?ex03 

http://www.ego4u.com/en/cram-up/grammar/auxiliary-verbs/exercises?ex04 

http://www.ego4u.com/en/cram-up/grammar/auxiliary-verbs/exercises?ex09