Correção de "I need to sleep by midnight''

The correct is ''I need to sleep by midnight'' or ''I need to sleep until midnight''?
Have any difference?
Which is correct and why?
Thanks!!!
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Avatar do usuário Donay Mendonça 49120 21 73 1139
Akands,

Sugestões:

I need to go to bed by midnight.
Avatar do usuário yagoag 20
Both are correct, but with completely different meanings.
I need to sleep by midnight means Eu preciso dormir à meia-noite, pela meia-noite, in the other hand I need to sleep until midnight means Eu preciso dormir até a meia-noite (ex.: you're going to bed at 5 PM and you'll sleep until midnight because your flight is at 3 o'clock in the morning).

edit: when you're talking that you are going to sleep, prefer to use go to sleep or go to bed (the second is more usual), but I guess that it isn't totally incorrect and the phrase would be completely comprehensible the way you've written.

Best regards!
Avatar do usuário Thomas 14290 7 58 283
I need to get to sleep by midnight.