______ and short of breath, Andy and Ruby were the first to reach the top of Mount Tai.
– 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 ________.
________, no one is sure who discovered America .