Are you sure__ that for yourself?Yes,I think__A.to doing；it B.to doing；so C.to do；it D.to do；so

Question

Are you sure__ that for yourself?
Yes,I think__
A.to doing；it B.to doing；so C.to do；it D.to do；so

Answer 1

选D
此题考查固定搭配
be sure to do一定要做某事
be sure of doing确信能做某事
第二个空表示对上文的提问表示肯定的回答,用I
think so.