PAST PERFECT CONTINUOUS
FORM:
The past perfect continuous is composed of two elements:
1. The past perfect of the verb to be (=had been)
2. The present participle (base+ing).
FUNCTION:
The past perfect continuous corresponds to the past, but with reference to a time earlier than 'before' of it. Again, we are more interested in the process.
QUESTION: Complete the following sentences with the right past perfect tense:
We __________________to open the door for five minutes when Jane found her key. The stranger thing was that someone ________________ us in the room.