is known to us all is that the Olympic Games will take place in Beijing.A. ItB. AsC.

问题补充：

is known to us all is that the Olympic Games will take place in Beijing.

A. It

B. As

C. what

D. which

答案：

A. It

B. As

(答案→)C. what

D. which

解析：句意:我们大家都知道的是的奥运会将在北京举行。is known to us all 是主语从句，它缺少主语，故用代词what来充当主语。这个句子的同义句为：（1）Asis known to us all , that the Olympic Games will take place in Beijing.（2）_Itis known to us all that the Olympic Games will take place in Beijing.故选C 。