They often stay up, reviewing their lessons, books all over the desk.
| A．spreading | B．spread |
| C．are spreading | D．to spread |
13. — How do you keep fit?
— By having a healthy diet and _________ regularly.
| A．turning out | B．working out | C．giving out | D．going out |
12. Having finished their morning work, the clerks stood up behind their desks, ________ themselves.
| A．expanding | B．extending | C．expressing | D．Stretching |
11. ________ no need for us to discuss the problem again. It has already been settled.
| A．It has | B．There is | C．It is | D．There has |
10. — How old are you, madam?
— If you _______ know, I’m twice my son’s age.
| A．can | B．must | C．may | D．Should |
9. We forbid _____ in the reading room. That is, you are forbidden _____ in the reading room.
| A．to smoke; to smoke | B．to smoke; from smoking | C．smoking; smoking | D．smoking; to smoke |