The existing version will remain valid within its expiration date.

现版永居证在有效期内仍可继续使用。

How long does your offer remain valid? I need some time to get my supervisors on board with this plan.

你们的报价多长时间有效？我需要一些时间让我的主管来参与这次购买计划。

Yet the fundamental principles remain valid.

然而，基本原则仍然有效。

The additionality of a project, the certainty with which you know that carbon will be avoided or removed, the duration of time over which your investment will remain valid.

项目是否有额外的减排效果，投资人是否对碳抵消或碳移除抱有信心，投资的有效期。