be on guard against

基本解釋

How to be on guard against pickpockets and swindlers?
乘坐地鐵時如何防范扒竊和詐騙行為？
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Thus, you should be on guard against this confused mapping.
因此，您應該謹防這種有混淆的映射。
And I will be on guard against two evils: hastiness and indecision.
而且我將防范兩個邪惡：草率、優(yōu)柔寡斷。
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One of the things, by the way, that Eikhenbaum does in passing is remind us that we should be on our guard against thinking that sound is onomatopoetic--that is, that it reflects the meaning of what it's talking about.
艾肯鮑姆在書中提到,他特別提醒我們,不應該贊同擬聲現(xiàn)象，擬聲就是認為聲音能反應它所表達的意思。
耶魯公開課 - 文學理論導論課程節(jié)選

Such regimes are therefore inherently belligerent and democratic nations must always be on guard against them.
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We must be on guard against cybersecurity becoming cyber-pork as well.
FORBES: Cybersecurity Theater vs. The Real Thing
In fact, we should be most on guard against ourselves.
FORBES: Magazine Article