Past perfect continuous tense

Structure of past perfect continuous
positive negative question
I / you / he / she / it / we / they
had been going.
I / you / he / she / it / we / they
hadn’t been going.
Had
I / you / he / she / it / we / they
been going?
Past perfect continuous – common mistakes
Common mistakes Correct version Why?
I had working hard, so I felt very tired.
I had been worked hard, so I felt very tired.
I had been working hard, so I felt very tired. The form of the past perfect continuous is had + been + verb (-ing).
I had been hearing the song many times before. I had heard the song many times before. Some verbs (called stative verbs) are not normally used in the continuous form, e.g. know, like, understand, believe, hear, etc.