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

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

C

句意为：他写了一封信。在信中他解释了事故中发生的一切。据分析，“he explains what had happened in the accident.”部分为一定语从句，修饰先行词a letter。而且该从句本身主(he )--谓(explains )--宾(what had happened in the accident)成分齐全，缺少的是地点状语。所以用关系副词where. 【考点定位】定语从句的考查。