1. The Past Perfect Tense
We form the Past Perfect with had and the past participle (Had + Past Participle)
- Express the past action, already finished when another past action happened
E.g. I met them after they had divorced each other.
- Emphasize the result of an activity in the past
E.g. I had been to London twice by the time I got a job in New York.
- Show two events in the past that are linked
E.g. I couldn't take my flight because I had forgotten my boarding pass.
2. The Past Perfect Continuous Tense
We form the Past Perfect Continuous with had been and the -ing form of the verb (Had been + V-ing)
- Express a past action which started in the past and continued to happen after another action or time in the past
E.g. Sara had been working here for two weeks when she had the accident.
- Emphasize the duration of an activity in the past
E.g. Richard needed a holiday because he had been working hard for six months.
- Show the cause of a past action
E.g. I had been travelling all night, so I was tired.