— I am taking the college entrance examination next week.— ____!
It is______ of you to cooperate with such a bad man.
The boss ______ the worker how to do it, or the accident couldn’t have happened.
In the 1930s, the two countries were at ______ war, and his father was fighting at _____ front.
Don't leave for there until__________ to do so.
Tom’s teacher kept on telling him to practise speaking English, but _______ didn’t work.