..It is difficult to_______a conversation with someone who only says "Yes" or "No".A. keep up B.hold up c.pick up D.make up
In 1948, three American scientists invented ____ transistor, which is ____ small electronic device to control an electric current.
I don’t understand why the boss should __________ the girl, because in my opinion, it was her fault that caused the loss.
Our team _______ five persons.
He _______ gas a mile from home.
I want to go the party, but __________ I ought to stay studying.