Tom, clean up the broken glass _________ someone walks on it.
Look at the new computers, of ______ none are produced abroad.
Theory is based on practice and ________ serves practice.
—How many of them do you want to act in the play?—_______ , and still a large number needed!
Since no other way to escape from the flood, ____ only safe thing is to take ____chance.
—Would you mind my using your bicycle for a while?— _________, but do return before 11.