问题
选择题
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 it is
答案
答案:A
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 it is
答案:A