Question

 Smoking, which may be _______ fun for some people, is _______ cause of discomfort for  people around him. 

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

Answer 1

解析：选A。考查冠词。句意为：吸烟对某些人来说也许很好玩，而实际上却使得周围的人感觉不舒服。fun是不可数名词，不与不定冠词a连用；吸烟是引起人们不舒服的因素之一，因此在cause前加不定冠词a。