保安人员对宾客要有礼貌，语言要（）。
参考答案：亲切
学校买了2张桌子和8把椅子共用去960元，每张桌子240元，一把椅子多少元？
Every boy and every girl as well as some teachers who ___ to visit the museum _____required to be at the bus station at 6:30.
A．are ; is
B．are ; are
C．is ; are
D．is ;is
