“Cambridge” is a famous university ___ a long history

Do you mind my smoking here—_________. Look at the sign. It says, “No Smoking.”

Urban crowdedness would be greatly relievedif fares ______ on public transport were more reasonable.

The day will come _____ the people all overthe world will get rid of poverty

You had better book rooms at the hotel in advance_____you should find no room on your arrival