Complete the sentences using past simple or past continuous.

1) We were working in Russia. (Past Continuous for a process in the past) 2) She had breakfast when the telephone rang. (Past Simple for a completed action interrupting another, Past Simple for the action itself) 3) When they left the gallery, the sun was shining. (Past Simple for a sequence of events, Past Continuous for the background action) 4) The students laughed when the professor came in. (Past Simple for both actions) 5) While the children were sleeping, their parents were watching TV. (Past Continuous for both simultaneous actions) 6) It started to snow while she was coming back from the opera. (Past Simple for an action, Past Continuous for the background action) 7) When Pete opened the door, it was raining. (Past Simple, Past Continuous) 8) While Evgeny was sunbathing, his wife was swimming in the sea. (Past Continuous for both actions) 9) She heard a loud bang while she was talking to her friend. (Past Simple, Past Continuous) 10) While he was taking a shower, his cats were eating his steaks. (Past Continuous for both actions) 11) When I texted, the school bus arrived. (Past Simple for both actions) 12) Ilya broke his leg while he was skateboarding. (Past Simple, Past Continuous) 13) He was listening to music while he was cooking breakfast. (Past Continuous for both actions) 14) My sister was driving at 120 km/h when a policeman stopped her. (Past Continuous, Past Simple) 15) The boy noticed that a girl was watching him. (Past Simple, Past Continuous) 16) My granddad fell off the ladder while he was painting the ceiling. (Past Simple, Past Continuous) 17) While they were waiting, they were surfing the Net. (Past Continuous for both actions) 18) Tim became sick while he was traveling in China. (Past Simple, Past Continuous) 19) What were you doing when you heard about the accident? (Past Continuous for a longer action, Past Simple for a shorter one) 20) My sister said that she did not feel happy, so I talked to her. (Past Simple for a sequence of actions)