leave well alone meaning in English

不要画蛇添足

The present system has worked satisfactorily , so why change it ? my advice is to leave well alone
现有的这个制度运作得很美满，那麽什要改变呢？我的建议是听其自然。
The present system has worked satisfactorily , so why change it ? my advice is to leave well alone
目前这个制度执行情况令人满意，为什么要改变呢？我侍建议是听其自然。
Last week she ruined the whole job while trying to put right a small mistake , so this time she left well alone
上个星期她在纠正一个小错误时把整个工作都搞砸了，所以这次她保持原样不动了。
If you are not sure what to do , leave well alone , but try to help if they are not breathing or are bleeding heavily
如不认识怎样急救，不要尝试急救。不过，如果伤者呼吸停止或大量出血，你应该尝试急救。