【题目】The reason ________ he failed to make himself understood was ________ he was not good at speech.
A. for which, becauseB. that, that
C. which, becauseD. why, that
在线课程【答案】D
【解析】
考查定语从句和表语从句。句意：他没有让别人明白他的意思的原因是他不擅长演讲。本句为句型the reason why…is that………的原因是……。第一空why引导定语从句，表示“为什么”；第二空that引导表语从句，解释原因。故选D项。