The past perfect progressive tense is an extension to the past perfect tense and its structures. Past perfect progressive is used to demonstrate an action which continued for a specific period of time but stopped before another action.

Structure:


Subject + had + been + verb+ing + . . . . . + for/since + . . . . .+ before + subject + past simple tense

Alan had been playing cricket for 18 years before he retired.

Jack had been living in Sydney since 2010 before he moved to Melbourne.



Note: This tense can be replaced by the past perfect tense withdrawing for/since.