_______ to sunlight for too much time will do harm to one’s skin.
A. Being exposed B. Exposed
C. Having exposed D. After being exposed
The bell _______ the end of the period rang, _______ our heated discussion.
A. indicated; interrupting B. indicating; interrupting
C. indicating; interrupted D. indicated; interrupted
The research is so designed that, once _______, nothing can be done to change it.
A. begins B. having begun C. begun D. Beginning
In Dali Mr Green was so struck by the beauty of _____nature that he stayed for _____third week.
A.the ; the B. the ; a C. 不填；the D. 不填；a
—Try not to work yourself too hard. Take it easy.
—Thanks. ________.
A. So what? B. No way C. What for D. You too
—Did you ask Tom for help?
—I ________. —I managed perfectly well on my own.
A. needn’t have B. don’t need to C. didn’t need to D. needn’t
