I should probably warn you, the past tense is the most complex tense in English and you can write a dissertation on it. Your question is a little broad :( However I might be able to help a tiny bit.Originally Posted by student12
First off, "have been" is just a plural form of "has been".
The first case "had been"
this tense is used to compare the relativity of one occurrence in the past to another. You cannot use this tense to describe just one action. Had been is used to define one thing that occurred at a previous point in time before another thing, but both things began, occurred and ENDED in the past. That's the giveaway. This is called the past perfect.
We had been walking for 4 hours when someone finally decided to give us a ride.
I had been writing for what seemed like days, my arm felt like it was going to fall off!
Susan had not had such a satisfying meal since she killed that deer last winter.
Has/Have been denotes an action that began and occurred in the past, but is still occurring for all we know. This is the Past Perfect Contiunuous. Some people call it the Past Progressive which isn't totally correct but it's not totally incorrect either.
We have been enrolled at this university for 2 years now.
I have not been to his house in forever !
The guy at the bar has been trying to score all night.
You guys have been making noise all night. Please go to bed now.
I hope this helps you a little :)