More than 800,000 Chinese overseas students have returned in the last five years, with the annual number ______ by an average rate of 36 percent each year.

With food and gunpowder       short, the soldiers are suffering from hunger and danger of being attacked by the enemies at any time.

 --What do you think made Celia so happy?--______ a prize in the recent competition.

---Come on, let’s go for a drink. ---Sorry. With so many problems _____ my mind, I can’t take a break.

In the reading room, we found her 　　　 at a desk, with her attention _____ 　　　 on a book.