is not a valid date

The valid-from date is a BPEL extension, standard BPEL does not provide it.

起始有效日期是一个 BPEL 扩展，标准 BPEL 并没有提供它。

You decide whether you want a card that is valid for 24, 48 or 72 hours. The card will not be valid until it is stamped with the time and date the first time you use it.

你可以自己决定购买有效期为24、48或72小时的卡，而该卡在盖章标明你第一次使用它的那个日期和时间才开始生效。

A voting trust is valid for not more than 10 years after its effective date unless extended under subsection (c).

除非依据(c)小节的规定延期，投票信托组织的有效期自生效日起不得超过10年。