Verbos auxiliares

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 thatbe 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
You can tell that in the following sentences be is an auxiliary because it is followed by anotherverb (the full verb). (For progressive forms use the "-ing" form of the full verb; for passive voice, use the past participle of the full verb.)
Progressive Forms
Present Progressive:He is playing football.
Past Progressive:
He was playing football.
Present Perfect Progressive:
He has been playing football.
Past Perfect Progressive:
He had been playing football.
Passive
Simple Present/Past:The house is/was built.
Present/Past Perfect:
The house has/had been built.
Future I:
The house will be built.
"be" as a full verb
The verb be can also be a full verb. In this case, it's notfollowed by another verb. If be is used as a full verb, we do not need an auxiliary in negative sentences or questions.
positive sentence:
They are fifteen years old.
negative sentence:
They are notfifteen years old.
question:
Are they fifteen years old?
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 compoundtenses 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.
Compound Tenses - Passive Voice
Present/Past Perfect:
The...