to sunlight for too much time will do harm to one’s skin so you should make it a rule t

问题补充：

to sunlight for too much time will do harm to one’s skin, so you should make it a rule to get your skin creamed before going out in summer.

A. Exposed

B. Having exposed

C. Being exposed

D. To expose

答案：

A. Exposed

B. Having exposed

(答案→)C. Being exposed

D. To expose

解析：句意：过长时间暴露于阳光下会对人的皮肤造成损伤，因此，夏天外出前涂上防晒霜应该成为你的习惯。根据will do harm to是主句谓语确定空处应该是句子主语。A项不能做句子主语，排除；根据句意应是被暴露于阳光下，应是被动，B和D是主动，也排除。故C正确。