I don’t know the reason _______ you were absent from the meeting, and I am not sure that someone will tell me the reason _______ you haven’t told me.
______ their life in the past, ours is much better.
The soldiers ran as fast as they could, ______ to catch the fleeing enemies.
______ for half a month, the town was running out of food and clothing.
_______ for the coming examinations before, I have no time for the film.
The books _______ belong to Mr. Smith.