It has been announced that candidates remain in their seats until all the papers have been collected.
| A．shall | B．can | C．should | D．must |
8. Your understanding on the theory is_________satisfactory. You must read more after class.
| A．far from | B．up to | C．along with | D．free of |
7. This year is very special, _______Chinese New Year' s Day falls on Valentine' s Day.
| A．once | B．while | C．if | D．For |
6. How can you call it home? It' s__________a house.
| A．hardly | B．rarely | C．badly | D．Occasionally |
5. When _______about one of the biggest concerns today, many people mention the sharp rise in prices.
| A．asking | B．to ask | C．having asked | D．Asked |
4. People begin to know that most environmental problems exist because necessary measures for preventing them _______taken in the past.
| A．are not | B．were not | C．hadn't been | D．wouldn't be |