PRESENT PERFECT OR PAST SIMPLE?
1. DIFFERENCES IN USE
PRESENT PERFECT PAST SIMPLE
Single or repeated actions in the past, when
we don't know the date of the action or it
isn't important:
I've driven an automatic car before
We've been to the theater many times
Time expressions: before, ever, already, just
and yet
Single or repeated actions that happened at
a definite time in the past:
I drove a racing car in the summer
We went to the theater twice last month
Time expressions: yesterday, last month, in
2007, etc.
Situations that started in the past and are
still continuing:
Tom has worked at the garage for two
years
(He's working there now)
with for + period of time, or since + date
Situations that started and finished in the
past:
Alex worked at the garage for two years
(He isn't working there now)
with for to say how long the situation lasted
One or more completed actions in a time
period that is still continuing:
He's sold fifteen cars this month
Time expressions: this morning / evening,
today, so far, etc.
Completed actions in a time period that is
finished:
He sold twenty cars in August
I sold my Toyota two weeks ago
with ago to mean '(a period) before now'