hit-and-miss

音标发音

Experiments have suggested that this approach is hit-and-miss, with some organisations more proactive than others.
实验表明，这种做法更像碰运气，总有某些机构比其他更主动一些。
For a rather less hit-and-miss strategy, we can use computer-led "rational design" modelling processes to make artificial enzymes from scratch.
除了这种无头苍蝇的方法，我们还可以使用基于计算机的“理性设计”模型从零开始设计新酶。
Barnum understood that hit-and-miss advertising doesn't work, but a consistent message, told over and over, hits its mark .
巴纳姆了解乱枪打鸟式地打广告是没用的，可是持续发出始终如一的讯息就能正中标的。

As a result, recent attempts by Democrats to shore up their support among Latinos have had a hit-and-miss feel.
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The still photos came out a bit on the washed-out side at times, but this can often be a hit-and-miss feature of sports cams.
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What was once a hit-and-miss affair is becoming increasingly systematic.
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If something is hit-and-miss, you cannot depend on it to be of good quality, on time, accurate, etc.