He made another wonderful discovery, ___
题型:选择题
问题:
He made another wonderful discovery, ____ of great importance to science.
A.which I think is
B.which I think it is
C.which I think it
D.I think which is
He made another wonderful discovery, ____ of great importance to science.
A.which I think is
B.which I think it is
C.which I think it
D.I think which is