adverb
BAD : When we came out the restaurant, it was half past eleven.
GOOD : When we came out of the restaurant, it was half past eleven.
BAD : She suddenly stood up and ran out from the room.
GOOD : She suddenly stood up and ran out of the room.
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verb of movement + out : 'I'm afraid Mr Baker has just gone out.'
verb of movement + out of + somewhere (NOT out or out from ): 'I've just seen Mr Baker going out of the building.'
In informal conversation, out is sometimes used instead of out of : 'I saw someone jump out the window.' However, careful users consider this to be incorrect.