Definition
to retire for the night
去睡覺
It was getting late, so John decided to turn in early.
天色已晚，所以約翰決定早點去睡覺。
I'm really tired tonight; I might turn in by eight.
我今晚真的很累，可能會在八點前睡覺。
He maintains a good routine, turning in before ten every night.
他保持著良好的作息，每晚十點前睡覺。