不属于遗传性疾病的是： [ ]
A．感冒
B．白化病
C．色盲
D．苯丙酮尿症
答案：A
The airline stewardess (空姐) said to passengers on ______ with a beautiful smile, “welcome _________!”
A．aboard; board
B．board; aboard
C．board; board
D．aboard; aboard
A．变大
B．变小
C．不变
D．无法确定是否变化
