Помогите с решением очень срочно нужно

1/ The thief was arrested by the police at the scene of the crime. 
2/ The tickets hadn't been sold by that time. 
3/ Have many homes been destroyed by the volcano? 
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1/ These pictures aren't often exhibited when we are in the gallery. 
2/ These pictures weren't exhibited when we were in the gallery two years ago .
3/ These pictures hadn't been exhibited since 1999 when we were in the gallery. 
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1/ Tomatoes are sold in the market per 40 rubles a kilo.
2/ This phenomenon hasn't been studied yet.
3/ Will the new hospital be built in our city?

1 The thief was arrested by a police at the scene of the crime.
2 The tickets hadn't been sold by that time.
3 Had many houses been destroyed on the island by the volcano?
N2
1 These pictures are not often exhibited when we are in the gallery.
2 These pictures were not exhibited when we were in the gallery two years ago .
3 These pictures haven't been exhibited since 1999 when we were in the gallery.
N3
1 Tomatoes are sold in the market per 40 rubles a kilo.
2 This phenomenon is not studied yet.
3 If the new hospital will be built in our town?