ast Perfect Continuous Tense
The past perfect continuous tense is formed with the past perfect tense of the verb to be (= had been) + the present participle (–ing).
Example: I had been praying.
The past perfect continuous is used:
for an action that occurred over a period of time in the past.
Example: He had been playing saxophone in a jazz band.
for an action which started and finished in the past before another past action. Here, since or for is usually used.
Example: Jack got a job at last. He had been looking for a job since last year.
Example: He and his brother had been playing badminton together for ten years before one of them got married.
in reported speech, the present perfect continuous tense becomes past perfect continuous tense.
Example: John said, "We have been traveling by train across Europe."
Example: John said they had been traveling by train across Europe.