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
B:valuable
C:worthless
D:worthwhile
正确答案是：
同类题型
Don’t play on the road. It’s dangerous.—_______________________________.
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Why did you take a taxi____you could come here by bus?
good treatment, Linda is beginningto_________ and will soon recover.
They are ________ little girls _________ they can’t dress themselves.