1．They all have their own characteristics, but they all share ___ spirit of creativity and scientific skill that have made Zhongguancun ____ success．

A．the;   /      B．a;   /   C．a;   the   D．the;    a  

2．The flu is believed _____by viruses that like to reproduce in the cells inside the human nose and throat．

A．causing        B．being caused       

C．to be caused  D．to have caused

3．____ in a white uniform, he looks more like a cook than a doctor．

A．Dressing        B．To dress       

C．Dressed        D．Having dressed