In the final exam of last term, our maths teacher Mr.Wu gave us ________we all couldn’t work out
A.such a difficult problem that
B.so a difficult problem as
C.so difficult a problem that
D.as difficult a problem as
网友回答
D解析本题考查状语从句。本题考查so/as + adj. + a/an + n. + as或such + a/an + adj + n. + as结构，根据其结构，故选D。