Student or Learner
I want to ask you
when I should use the(past perfect tense-present perfect tense-past continuous)
And how I should use them??
have already seen the Grammar Glossary?
Read the Glossary, and then come back if there are any questions left, or try to give any specific examples you'd like to get your mental teeth into.
Not that nobody wants to respond to your query, but it's easier and more efficient for you to work on specific examples.
I'm sure someone will come to your aid.