房卡丟了，，請幫開門：The room card was left inside the room , could you please make the door open？
在酒店前臺請服務員幫自己開房，， Piease help me to open a room.
這是簡化版的，非常生硬，，當然壹般都用Excuse me ?I want book a hotel room. Do you have the rest of the room？