to sunlight for too much time will do harm to your skin.
A. Exposed
B. Having exposed
C. Being exposed
D. After being exposed
网友回答
A. Exposed
B. Having exposed
(答案→)C. Being exposed
D. After being exposed
解析：句意：在阳光下晒太长时间对人的皮肤有坏处。在这个句子中，will do是谓语，缺少主语，要用动名词作主语。在非谓语动词中，用动名词或不定式来作主语，而分词和介词短语不能作主语，因此A、B被排除。expose与one's skin是动宾关系，所以要用动名词的被动式being exposed。所以选C。