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!!!
Editado pela última vez por Donay Mendonça em 19 Out 2011, 11:10.
Razão: Correção

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3 respostas
Donay Mendonça 23 108 1.6k
Akands,

Sugestões:

I need to go to bed by midnight.
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!
Thomas 7 61 291
I need to get to sleep by midnight.