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To go to bed or to fall asleep. I'd been getting up so early all week long that I was ready to sack out by 11 on Friday night. Jonathan sacked out in the passenger seat, so I had to drive nearly the whole way in total silence.
asleep. Mary is sacked out in her room. Here it is ten o'clock, and you are still sacked out!
mod. asleep. Here it is ten o’clock, and you are still sacked out!