The professor’s research finally proved
题型:选择题
问题:
The professor’s research finally proved to be ______, though he had spent a lot of money on it.
A.priceless
B.valuable
C.worthless
D.worthwhile
The professor’s research finally proved to be ______, though he had spent a lot of money on it.
A.priceless
B.valuable
C.worthless
D.worthwhile