—I didn’t hear you come in just now.—That’s good. We tried ____any noise, for you were sleeping.
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) .