【题目】The reason _____ he was late for school was _____ he had to send his mother to a hospital.
A. that; why B. why; because
C. why; that D. that; because
在线课程【答案】C
【解析】
试题分析：C考查定语从句和表语从句。本题第一空是由why引导的是定语从句，修饰名词the reason，后面定语从句的句子结构很完整，所以使用关系副词。第二空是that所引导的表语从句，that在句中不充当任何成分，只起引导和连接的作用。句意：他上学迟到的原因是他要送妈妈去医院。故选C。