Last term our maths teacher set so diffi
题型:选择题
问题:
Last term our maths teacher set so difficult an examination problem _____ none of us worked out.
A.that
B.as
C.so that
D.which
Last term our maths teacher set so difficult an examination problem _____ none of us worked out.
A.that
B.as
C.so that
D.which