---I bought three DVD copies of the film Avatar and now is left. Somebody just borrows something and never returns. ---Things like that happen all the time.
The government has taken some measures to reconstruct the earthquake-hit areas, but it must be some time ________ everything returns to normal.
________ twice a year, whether it is a car or a bus or a truck, is the rule that every driver must obey in this city.
We agreed to accept ________ they thought was the best professor in the college.
I don’t know who invented ________ telephone. It’s really ________ most useful invention.
I know a little bit about the city as I __________ there for one year in my youth.