这句英语是什么意思

Question

The building, in front of which sat a boy, was a school.

Answer 1

The building, in front of which sat a boy, was a school.
前面坐着一个男孩的那幢建筑是一所学校。
in front of which sat a boy，是一个非限制性定语从句， 其作用相当于一种插入语或者对先行词的一种解释，和先行词之间只有比较松散的关系，去掉了也不会影响主句的意思，句中常常用逗号将其与主句分开，用法其实与限制性定语从句极为相似，只是不能用that做修饰词。

in front of which sat a boy，同时也是一个倒装句。in front of介词提前，句子全部倒装。即把谓语动词sat提到了主语boy之前。

Answer 2

前面坐着一个男孩的那幢楼是一所学校。

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