John’s success has nothing to do with good luck. It is years of hard work has made him a g

问题补充：

John’s success has nothing to do with good luck. It is years of hard work has made him a great scientist today.

A. that

B. when

C. which

D. why

答案：

(答案→)A. that

B. when

C. which

D. why

解析：

这题考查强调句的用法：It’s+强调部分+that…,这句话强调的是主语，years of hard work，句意是：约翰的成功和幸运无关，是多年的努力使他成为伟大的科学家。选A。