1/reservation释义：
n. 预约，预订保留
2/例句：
Your reservation will be retained for 4 hours and will be cancelled automatically after the time-out.
您的预订将保留4小时，超时后自动取消。
3/reservation的形容词有：
hotel reservation酒店预订订旅馆
make a reservation预定（房间、票）预约
without reservation无保留地
