It was along the Mississippi River Mark Twain spent much of his childhood.A. how B. which

It was along the Mississippi River Mark Twain spent much of his childhood.
A. how
B. which
C. that
D. where

A. how B. which(答案→)C. thatD. where解析：通过分析句子结构，可知这个句子中包含一个强调句。题目中含有It was，出现这样的结构，首先要考虑它是不是强调句。如果把这种句型结构划掉后，应该是一个完整无缺的句子；这也是判断强调句型与其它从句的方法。假设它是强调句，去掉it was和空格处，剩下的句子经过调整语序后变成Mark Twain spent much of his childhood along the Mississippi River.经过调整语序是一个完整的句子，所以是强调句型，对地点状语进行强调。强调句的结构It is/was+被强调部分 + that + 句子的其他成分，如果被强调的部分是人，可以用who代替that。

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