is known to us all Lu Xun is famous for his great works a great writer. A. It; that; for

问题补充：

is known to us all Lu Xun is famous for his great works a great writer.

A. It; that; for

B. It; that; as

C. As; / ; for

D. As; that; as

答案：

A. It; that; for

(答案→)B. It; that; as

C. As; / ; for

D. As; that; as

解析：考查it做形式主语，主语从句和介词：句意：我们都知道鲁迅因为他做为伟大作家的伟大作品著名。从第二个空，可知是“作为”，排除AC，D项as，引导的是非限制性定语从句，而从句子结构看不是，选B，it是形式主语，that引导的是真正的主语从句，选B。