Do it as __.
In fact, is really a hard job for the police to keep order in an important football match.
They considered a computer, which was considered a great help in their work.
The number of people invited __________ fifty, but a number of them _______ absent for different reasons.
The place was flooded ________ it had been raining for several weeks.
Mr. Smith has been here for only a few days, so he hasn’t left a deep impression _____ us.