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.
同一个知名品牌的比较，才能让潜在客户明白你的产品和服务是如何满足他们的需求的。
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.
上司喜欢你是很好，但是在面对关系公司发展成功的重要挑战时，仅仅取得上司的喜欢，以及具有大家早已知道的办事能力还是不够的。
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.
笔者发现，如果进行逆向构思，把电子的荷质比作为已知量时，可重新进行理论推导从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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