Present Perfect Simple!

The present perfect simple is formed with: has/have + past participle.

Ex:
You have seen that movie many times.
Have you seen that movie many times?
You have not seen that movie many times.

We use the present perfect to say that an action happened at an unspecified time before now. The exact time is not important. You can't 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.

Ex:
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.

Credits: Present perfect simple