in an emergency

基本解释

If you're fit enough to open the door in an emergency, you can be the first person out.
如果你足够适合在紧急情况下打开这道门，你可以当第一个跑出去的人。
In an emergency they could and should have done whatever was necessary to prevent the system from collapsing.
在紧急情况下，它们能够也应该采取一切必要措施，以预防金融体系崩溃。
The inability to restore from a backup in an emergency situation will have serious consequences for your company and probably for you as a DBA who is responsible for these tasks.
如果在紧急情况下无法从备份中还原，对于公司而言，会带来很严重的后果，对于负责这些任务的 DBA 而言，后果可能也很严重。

The new capsule could also be used if astronauts need to leave the station in an emergency.
This time you're a doctor in an emergency room and six patients come to you.
这次你是一名急诊室的医生,有天送来了六个病人。
耶鲁公开课 - 公正课程节选
Moreover, you might get hit by an illness and then you could be in desperate trouble that you will die unless you get some kind of emergency care, which might be very expensive.
还有，你可能染上重病,并且深陷绝境,以致你会因此而死去,除非你能获得异常昂贵的，紧急护理。
耶鲁公开课 - 金融市场课程节选

So in an emergency, you can restore your information technology (IT) environment in a snap.
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