◎ 题干
The acid rain is one of the chain reactions that ______ by environmental pollution .    
[     ]

A. is come about    
B. is caused  
C. are given birth  
D. are brought about

◎ 答案
查看答案
◎ 解析
查看解析
◎ 知识点
    根据n多题专家分析,试题“The acid rain is one of the chain reactions that ______ by environmental pollution.[ ]A. is come aboutB. is caused C. are given birthD. are brought about …”主要考查了你对  【动词短语】  等知识点的理解和应用能力。关于这些知识点的“档案”,你可以点击相应的链接进行查看和学习。