known quantity

基本解释

Comparisons to a known quantity can help prospective customers understand where your product or service fits in the range of solutions they are considering.
同一個知名品牌的比較，才能讓潛在客戶明白你的産品和服務是如何滿足他們的需求的。
It's good that the boss likes you, but when faced with serious challenges to the ongoing success of the company, being a liked, known quantity is not enough.
上司喜歡你是很好，但是在麪對關系公司發展成功的重要挑戰時，僅僅取得上司的喜歡，以及具有大家早已知道的辦事能力還是不夠的。
This found that if the reverse idea of the electron charge-mass ratio as a known quantity, it can re-theoretical derivation, and thus obtain the value of the vacuum in the speed of light.
筆者發現，如果進行逆曏搆思，把電子的荷質比作爲已知量時，可重新進行理論推導從而得到真空中的光速值。

Hardly an inspiring way of choosing a candidate, but Republicans apparently like a known quantity.
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G. was such a known quantity, how on Earth is someone going to fill those shoes?
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We put a known quantity up there, " says Kaufman, "to keep the emotions at a lower level.
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