1. The arsonist (had removed) all the valuables before she set fire to the house.
2. They (had robbed) five different banks when they were arrested.
3. The shoplifter (had been) a regular customer for years before she was caught.
4. We (had just got) back home when we realized someone was in the bedroom upstairs.
5. The burglars had left when we (came) back home; the house was empty!
6. As soon as the police (had arrived), they looked for fingerprints.
past simple, past perfect, past perfect simple or past perfect countinuous.
Olga(1)_____ (got) home late that night. She(2) ____(had) her dinner and then sat to watch a film on television. She(3) _____(had had) a long, tiring day at work and was looking forward to getting to bed early. She lived alone and lately (4)____(has been) a little worried, as there (5)_____ (were) a number of break-ins in her building. She (6)_____ (had been watching) the film for a few minutes when she (7)_____ (heard) a strange noise in the kitchen. She began to worry. (8)______(Had she/remembered) to lock the front door? She wondered. She slowly (9)_____(got up) and headed towards the kitchen. She turned on the light and (10)_____(saw) a bowl of fruit tipped over in the kitchen. Pretty sure she (11)_____(had not done) that earlier, she began to panic. Suddenly, her cat (12)_____(appeared). Relieved, she picked him up and went back into the living room to watch her film.