一朝被蛇咬，十年怕井绳

yī zhāo bèi shé yǎo , shí nián pà jǐng shéngyizhaobeisheyao,shinianpajingsheng

1. (lit.) once bitten by a snake, one is scared all one's life at the mere sight of a rope (saying)
2. (fig.) once bitten, twice shy

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