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Complete the sentences with the correct form of the verbs in brackets (Past Perfect Tense or Past Perfect Continuous Tense).
Mary ______________(not / finish) her dinner when her sister came.
When she come to the garage, the mechanic __________ (not / repair) her car.
Liza ___________ (paint) the walls all day before she finished them.
The boys ____________ (finish) doing their homework by eight o`clock.
Peter _____________ (work) as a driver for thirty years when he retired.
They ___________ (watch) TV for a quarter of an hour when the door bell rang.
Tom __________ (return) home before the storm began.

Mary (had not / finished) her dinner when her sister came. When she came to the garage, the mechanic (had not / repaired) her car. Liza (had been painting) the walls all day before she finished them. The boys (had finished) doing their homework by eight o`clock. Peter (had been working) as a driver for thirty years when he retired. They (had been watching) TV for a quarter of an hour when the door bell rang. Tom (had returned) home before the storm began.