在参加风味餐宴请时，导游员要积极发表讲话，以活跃就餐气氛。 （ ）
参考答案：错
Henry had just given himself for lost ______ he was spotted by a ship.
A．when
B．while
C．as
D．after
纵隔摆动可出现在()
A．闭合性气胸
B．开放性气胸
C．张力性气胸
D．单侧多根多段肋骨骨折
E．创伤性窒息
