He wrote a letter ______ he explained what had happened in the accident. A．what B．which C.

He wrote a letter ______ he explained what had happened in the accident. A．what B．which C．where D．how

C


    
试题分析:句意：他写了一封信，在信里解释了事故当中所发生的事情。从结构判断是定语从句，从句中意思完整，不缺少成分，应该用关系副词，what、how不引导定语从句，故答案选C。

c 试题分析：句意：他写了一封很长的信，信中他解释了事故中发生的事情。这里用了定语从句，先行词是a long letter，定语从句中不缺少主宾表，缺少的是地点状语，所以用where引导定语从句。选c。