The ascertaining or fixing of the quantity, quality, position, or character of something.

弄清楚某事物的数量，质量，位置或特征。

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The quota thus restricts quantity supplied, causing price to adjust, in contrast to a tariff, which induces a quantity adjustment by fixing a higher domestic price.

与之相反，关税则是通过固定一个较高的国内价格来诱使数量进行调整。没人愿意帮你翻译，我是新手，我来翻翻看。

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Mr Powell works for EC Harris, one of the main firms of quantity surveyors who advise water companies on costs and estimates for price fixing negotiations.

BBC: Customers 'lost out' in water sell off