问题补充：
---I have tried very hard to find a solution to the problem, but in vain.
---Why not consult with Frank? You see, .
A. great minds think alike
B. two heads are better than one
C. a bird in the hand is worth two in the bush.
D. it’s better to think twice before doing something
答案：
A. great minds think alike
(答案→)B. two heads are better than one
C. a bird in the hand is worth two in the bush.
D. it’s better to think twice before doing something
解析：A. great minds think alike英雄所见略同， B. two heads are better than one两人智慧胜一人， C. a bird in the hand is worth two in the bush.一鸟在手胜于二鸟在林， D. it’s better to think twice before doing something三思而后行，根据句意：--我努力找一个问题的解决办法，但是徒劳。---为什么不询问Frank？所以选B符合句意。
