支气管哮喘的并发症有
A．自发性气胸
B．肺不张
C．肺气肿
D．肺心病
E．慢性支气管炎
参考答案：A,B,C,D,E
—Can you come and give us a talk on Thursday or Friday?
—I am afraid ______ day is possible. I am very busy these days.
A．either
B．neither
C．every
D．any
欲除去下列物质中的杂质（括号内为杂质），请写出所用试剂的名称．
O2（水蒸气）______；
NaNO3（NaCl）______．
