---Guess what! I have got the highest score in the final exam.
---- Great! You ______ worked very hard and put a lot of energy into it.
| A．must | B．must have | C．should | D．should have |
19．China is a great country with a long history, ______ we all know it.
| A．as | B．so | C．but | D．and |
18．Development of economy ______ which our country attaches great importance, has drawn the attention of the whole world.
| A．with | B．for | C．to | D．in |
17． ______ others might have been satisfied, Dawson had higher ambitions.
| A．What | B．Why | C．Which | D．Where |
16．The dying man moved his lips as if ______ something, but it was too late for him to let out a single word.
A. to say B saying C. said D. having said
15． I got so angry at the news that I ______ her.
| A．should kill | B．might kill | C．must have killed | D．could have killed |