—Are there boats on the lake? --Yes, there are .
—How will your father go to Shanghai tomorrow? —I don’t know ____ .
Our classroom is tidy because it ____ every day.
Miss Lin ____ a lot of work for the poor area for about 10 years.
My friend John called and ____me to his party just now.
—I didn’t see you when I went to your office yesterday afternoon. Where were you? —I ____ a meeting in the meeting room.