散在湿性啰音，伴有哮鸣音呼气相延长（）.
A.支气管哮喘
B.支气管扩张
C.慢性支气管炎、肺气肿
D.支气管肺癌
E.特发性肺间质纤维化
参考答案：C
计算：a-2a=______．
Here ____ some girls. [ ]
A. is
B. are
C. have
D. am
