hit-and-miss

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Experiments have suggested that this approach is hit-and-miss, with some organisations more proactive than others.
實騐表明，這種做法更像碰運氣，縂有某些機搆比其他更主動一些。
For a rather less hit-and-miss strategy, we can use computer-led "rational design" modelling processes to make artificial enzymes from scratch.
除了這種無頭蒼蠅的方法，我們還可以使用基於計算機的“理性設計”模型從零開始設計新酶。
Barnum understood that hit-and-miss advertising doesn't work, but a consistent message, told over and over, hits its mark .
巴納姆了解亂槍打鳥式地打廣告是沒用的，可是持續發出始終如一的訊息就能正中標的。

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.