-- Why didn’t you do your math homework last weekend? -- My cousin borrowed my math book and didn’t_____ __it.
—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) .
--We’re going to a party for the exchange students this afternoon. --. And say hello to them for me.
_______ mother usually cooks for ________ at the weekend.