问题补充:
The math problem was difficult none of us worked it out.
A. very; that
B. too; to
C. so; that
D. enough; that
答案:
A. very; that
B. too; to
(答案→)C. so; that
D. enough; that
解析:句意:这道数学题太难了以至于我们中谁也做不出来。so...that...如此……以至于……;too...to...太……而不能,to后接动词。故选C.