What a pleasant surprise to see you here! I _______ you _______ Beijing.––Me too. But I _______ there next Friday.
You look quite tired. You’d better _____a good rest.
—How long have you _____the novel? —Three days.
—Listen!Helen is singing in the next room. —It _____be Helen .She has gone to Beijing.
Some people won’t realize the importance of their health _____they have lost it.
China has _____ area of about 9,600,000 square kilometers, including Diaoyu Island(钓鱼岛) .