问题补充:
there are a large number of chemical factories, the air is likely to be polluted.
A. Where
B. That
C. Though
D. As
答案:
(答案→)A. Where
B. That
C. Though
D. As
解析:考查状语从句。句意:在有很多化工厂的地方,空气很可能被污染。这里的where在句中做状语,引导的是地点状语从句。That不能引导状语从句,though引导的是让步状语从句。故A正确。