By this time next week, I will have worked on this project for twenty days.
I lost so much weight because I had begun exercising.
They have studied English for more than three years.

Nobody takes you away what you have danced

Present Perfect

Structure

Subject + Auxiliary HAVE or HAS + Main verb (past participle)

Use

We use the Present Perfect to talk about: experience, change, continuing situation. There is always a connection with the past and with the present.

Past Perfect

Structure

Subject + Auxiliary HAD + Main verb (past participle)

Use

Basically, when we use the past perfect, we are referring to a time earlier than before right now. It means that there must be two actions happening at different times in the past.

Future Perfect

Structure

subject + Auxiliary WILL HAVE + Main verb (past participle)

Use

It is uses to indicate that an action will have been completed (finished or "perfected") at some point in the future.