come on, guess that what 's the meanning of the phrase 'a long shot'解决方法

come on, guess that what 's the meanning of the phrase 'a long shot'.
a long shot.

what's its mainning?


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a long shot
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a long shot
1. 很少机会成功的尝试
------解决方案--------------------------------------------------------
a long shot
很少机会成功的尝试 
 
来自《英汉简明词典》
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远距离射击 ---> 引申为：这么做成功的可能性不大

It's a long shot to take CET 6 exam without passing CET 4.

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Fan sister W5!