these trials, people are ________assigned to a "treatment" group, which benefits from the project, and a "control" group, which does not.
– Shall I give you a hand?---I can handle it. ______.
– Did you telephone the manager’s office?---Yes. He _______ back by noon .
________, he has finished his job ahead of time.
I’d like _______ trip to Shanghai . Do you want to go with me?
.– I like your house very much.--- Thank you, but this house is ________.