Past Perfect Continuous Tense

The past perfect continuous tense is a verb tense that is used to talk about actions that were in progress for a period of time before another action in the past. It is also known as the pluperfect progressive tense.

Here are some examples of how to use the past perfect continuous tense:

To talk about actions that were in progress for a period of time before another action in the past: I had been working on my project for hours when I finally finished.
To talk about actions that were in progress before another action in the past but were interrupted: We had been playing tennis for an hour when it started to rain.
To talk about actions that were in progress before another action in the past but were completed: I had been reading a book when you called, but I put it down to talk to you.

Here are some rules for using the past perfect continuous tense:

The past perfect continuous tense is formed with the past perfect tense of the verb “to be” + the -ing form of the verb. For example, “I had been working” is the past perfect continuous tense of the verb “to work.”
**The past perfect continuous tense is used with time expressions that indicate the past, such as “before,” “by the time,” and “after.”

Here are some additional examples of the past perfect continuous tense:

I had been working on my project for hours when I finally finished.
They had been waiting for us for an hour when we finally arrived.
She had been studying for the test for weeks when she finally took it.
We had been talking for hours when we finally realized that we were talking about the same thing.
By the time I got to the store, they had already been selling out of bread for an hour.