屡试不爽 解释：
◎ 屡试不爽 lǚshì-bùshuǎng
[be found officious as often as it is tried;be often tried and often succeeded;effective every time it is used] 每次使用都有效;多次试验都不错
这种新农药效果良好,屡试不爽
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国语辞典屡次试验，结果都相同。如：「这个方法十分有效，屡试不爽。」
◎ 屡试不爽 lǚshì-bùshuǎng
[be found officious as often as it is tried;be often tried and often succeeded;effective every time it is used] 每次使用都有效;多次试验都不错
这种新农药效果良好,屡试不爽
屡次试验，结果都相同。如：「这个方法十分有效，屡试不爽。」