Re: stay up
That is fine. Other possibilities (not necessarily better) include:
Originally Posted by English4everyone
What's the latest (time) you have ever stayed up (till)?
What's the latest (time) you have ever been to bed?
What's the longest (time) you have ever stayed awake (till)?
Note the difference between staying up and staying awake. If you stay up, you have not gone to bed yet, but it is possible that you might doze off for a few minutes. If you stay awake, you do not go to sleep, but you could be in bed.
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