These vessels ride on a cushion of air when in use.

这些舰船在开动的时候，是浮在气垫上的。

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Pay special attention to the mold's maintenance when in use, making it dry dustless.

在使用过程中要尤其注重模具的保养，确保干燥、无尘。

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Pay special attention to the molds maintenance when in use, making it dry and dustless.

在使用过程中要尤其注重模具的保养，确保干燥、无尘。

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Ships no longer in use contain dangerous materials which can be released into the environment when they are taken apart.

VOA: special.2009.04.27

And when you actually wanna store information on disk, can you actually use, as we'll see in a moment, magnetic particles.

当你想在硬盘中存储信息时，我们将会用到后面，我们会谈论的一种称之为磁性粒子来实现它。

哈佛公开课 - 计算机科学课程节选

In another example, you can use a "when" question in order to ask about the timing of a specific event.

在下面这个例子中，你可以用When 问句来询问一个具体活动的时间。

When 课堂 - SpeakingMax英语口语达人

Even more important, servers can be moved around, even when in use.

ECONOMIST: Virtualisation

When in use, headphones are a safe distance from the implanted device.

CNN: Study: Headphones could interfere with pacemakers

All kitchen appliances (except the fridge) remain unplugged, as do the printer, stereo, cell phone charger, and a few other electronics, except when in use.

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