to be short

基本解释

But why does the time frame have to be short?
那我要問，爲什麽是“短期”的才能有傚？
"If you must have it, it needs to be short and well groomed," he cautions.
他警告說：“如果你非要這樣做的話，也要確保衚須要短而整齊。”
One of the things that everyone agrees about methane on Mars is that it has to be short-lived.
大衆普遍認同的一件事是火星上的甲烷的壽命極短。

And this may be cool enough to keep foods fresh, at least for a short time.
If we have a high frequency, what about the wavelength, long or short? All right. Good. So we should always be able to keep these relationships in mind.
如果頻率高，那波長是長還是短？,好，不錯，我們要記住這些關系,類似的。
麻省理工公開課 - 化學原理課程節選
There's a Midterm. That will be a short answer test that's intended to give you a chance to show how diligently you've been reading and coming to class.
我們會有一個期中考，會有一張簡答問卷,目的是能夠讓你們表現出,你們的勤勞，用功閲讀和按時上課。
耶魯公開課 - 現代詩歌課程節選

Simple exclusion of the opinion of front line people has long been proven to be short-sighted.
FORBES: Business Aviators - Is that all they are, or should be?