Grammar Choose the correct tense.
1 The robber had left/had been leaving
before the police arrived.
2 He was angry because somebody had
been taking/had taken his keys.
3 How long had you been waiting/had you
waited before the ambulance arrived?
4 By the time we got there, the firefighters
had put out/had been putting out the fire.
5 They were tired because they worked/had
been working all night.