问题描述：
base on用法
The professor could hardly find sufficient grounds___ his arguments in favour of the new theory.
A.to be based on
B.to base on
C.which to base on
D.on which to base
选D,为什么,
The professor could hardly find sufficient grounds___ his arguments in favour of the new theory.
A.to be based on
B.to base on
C.which to base on
D.on which to base
选D,为什么,
问题解答：
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