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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 come 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 been finishing 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.