Definition
to retire for the night
去睡觉
It was getting late, so John decided to turn in early.
天色已晚，所以约翰决定早点去睡觉。
I'm really tired tonight; I might turn in by eight.
我今晚真的很累，可能会在八点前睡觉。
He maintains a good routine, turning in before ten every night.
他保持着良好的作息，每晚十点前睡觉。