This is accomplished by having an exception list that is updated every time something changes between the LVs (formally known as CoW, Copy-on-Write).

快照由一个例外列表(exception list)来实现，每当LV之间出现差异时就会更新这个列表(正式的说法是CoW, Copy - on - Write)。

youdao

There is an exception to this rule, as some stressors continue over a long period of time, rather than occurring as a single event.

有一个例外到这一点，因为有些压力继续在一段长时期内，而不是作为一个单一的事件发生。

youdao

An exception to this rule is the case of a us citizen legally sponsoring a spouse in which the marriage at the time of the adjustment of status (I-485) is more than two years old.

这个规则的例外是美国公民的事例法律上主办婚姻在状态的调整之时的配偶(I - 485)超过二岁。

youdao

The only time this is an exception is when you combine specific types of polymers and metals with specific additive manufacturing processes.

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Now is not the time to carve out an exception and raise middle-class taxes, which is why you should pass this bill right away.

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