Perfect Tenses of Verbs
A
perfect tense usually indicates action that is
completed by a certain time. Each perfect tense verb combines a
simple tense form of have with the past participle of the main
verb. (The simple tense forms of have are these:
present--->has, have; Past--->had;
future--->will have.)
The
present perfect tense indicates action that began in
the past and continues in the present.
Roger has worked as a doctor
for five years.
The
past perfect tense indicates action that was
completed before another action in the past.
He had worked in a hospital
before he went to medical school.
The
future perfect tense indicates action that wil be
completed before an action in the future.
By next June, he will have
worked for a total of ten years.
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