47. Three hundred firemen raced to the hotel after a smoke detector ______ the alarm soon after midnight.
Do you know the boy _______ under the big tree?
The computer centre, ______ last year is very popular among the students in this school.
Mrs Smith warned her daughter ____ after drinking.
The murder was brought in, with his hands _______ behind his back.
It is no use _____to come now. He is busy.