15.We should prevent pollution_____happily. A.from living B.to live C.living D.to living 为什么是选B,不选A 呢 16.I’m examining the composition he has just finished_____the possible mistakes in it. A.to correct B.correct C.corrected D.correcting 还有这题也是选A,为什么这种题都是选动词不定式,而不选动名词呢。