Present Perfect
FORM
[has/have + past participle]
Examples:
You have seen that movie many times.
Have you seen that movie many times?
You have not seen that movie many times.
USE 1 Unspecified Time Before Now
We use the Present Perfect to say that an action happened at an unspecified time before now. The exact time is not important. You CANNOT use the Present Perfect with specific time expressions such as: yesterday, one year ago, last week, when I was a child, when I lived in Japan, at that moment, that day, one day, etc. We CAN use the Present Perfect with unspecific expressions such as: ever, never, once, many times, several times, before, so far, already, yet, etc.
Examples:
I have seen that movie twenty times.
I think I have met him once before.
There have been many earthquakes in California.
People have traveled to the Moon.
People have not traveled to Mars.
Have you read the book yet?
Nobody has ever climbed that mountain.
A: Has there ever been a war in the United States?
B: Yes, there has been a war in the United States.
Time Expressions with Present Perfect
When we use the Present Perfect it means that something has happened at some point in our lives before now. Remember, the exact time the action happened is not important.
Sometimes, we want to limit the time we are looking in for an experience. We can do this with expressions such as: in the last week, in the last year, this week, this month, so far, up to now, etc.
Examples:
Have you been to Mexico in the last year?
I have seen that movie six times in the last month.
They have had three tests in the last week.
She graduated from university less than three years ago. She has worked for three different companies so far.
