sign in

Từ điển Oxford Advanced Learner 8th

ˌsign ˈin/ˈout | ˌsign sbˈin/ˈout derived
to write your/sb's name when you arrive at or leave an office, a club, etc
•All visitors must sign in on arrival.
•You must sign guests out when they leave the club.
Main entry: ↑sign_derived