The professor could hardly find sufficient grounds________ his arguments in favor of the new theory.
A.on which to base | B.which to base on | C.to base on | D.to be based on |
推荐套卷
The professor could hardly find sufficient grounds________ his arguments in favor of the new theory.
A.on which to base | B.which to base on | C.to base on | D.to be based on |