请在起飞前至少一小时办理登机手续。

Please ___check ___in at least an hour before departure.

她必须为她的国际航班提前办理登机手续。

She had to ___check ___in early for her international flight.

你可以在航班起飞前24小时在线办理登机手续。

You can ___check ___in online 24 hours before your flight.