a fine line between something and somethingDIFFERENTif you say that there is a fine line between two different things, you mean that they are so similar that one can easily become the other 某事物和某事物之间只有一线之差 There’s a fine line between bravery and recklessness. 勇敢和鲁莽仅一线之差。
a fine line between something and something• It's a fine line between guilt and shame.• There's a fine line between clever and stupid and Warrant are nowhere near it.
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