hit or miss

基本解释

Keeping the information between the two tools synchronized was a hit or miss proposition.
保持這兩個工具間的信息同步是一個漫無目的的主張。
The network provides adequate coverage on the coasts (see map), but it's hit or miss in the middle of the country, and there are 12 states with no Sprint 4G service at all.
網絡在沿海地區提供了足夠的覆蓋率，但卻忽略了中部地區。在那裡，有12個州壓根就沒有Sprint的提供的4G服務。
Ideally, I would love to use TrueCrypt to encrypt my USB drives in their entirety, but since having admin privileges is always hit or miss when traveling, it's a risk I can't afford to take.
理想上我希望使用TrueCrypt來完整加密U磐，但是因爲在旅遊時開啓琯理員權限是很麻煩的事情，很難能每次都做到。

So it's this interesting scenario where it's probably hit or miss, certainly early on and as one of the clips they are indicated, these are the kinds of things where computers ideally have to learn overtime.
因此，這是一個有意思的事情,因爲它有可能是投其所好或者不對其胃口，儅然繼續,正如其中一個短片所示，這些東西需要計算機,花一些時間去學習。
哈彿公開課 - 計算機科學課程節選

Such books have a short shelf life and can be hit or miss.
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Some people make money by price speculation, but that is hit or miss.
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The job market, already hit or miss, would likely be put on pause.
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