Progress so far has been very good . ,we are sure that the project will be
pleted on time.
A. However
B. Otherwise
C. Besides
D. Therefore
网友回答
A. However
B. Otherwise
C. Besides
(答案→)D. Therefore
解析：考查副词：A . However然而B . Otherwise否则C. Besides此外，D. Therefore因此，句意：进展一直很好，所以我们一定能准时完成这个工程。选D。