2019年mpa考试英语真题——介词和介词短语1654

{01}It is necessary to explain your theory _____, otherwise the  audience won"t make sense of what you are trying to get across. A.on purpose B.at length C.at random D.on average 解析：
试题分析：句意：有必要详细地解释你的理论，否则观众就不会明白你想要表达的意思。A. on purpose故意地；B. at length详细地；C. at random随意；D. on average平均。故选B。
考点: 考查介词短语的用法。 
本题选B。