The chairman thought _____ necessary to invite Professor Smith to speak at the meeting.
. She has a strong belief that she will ______ her country to take part in the Olympic Games.
With all his efforts, ______ he made such great progress.
______ is even more important is that water began to appear on the earth’s surface.
I regret ______ you that you have not been chosen for the performance.
—Waiter, ______ ?—Sure. Here’s your bill.