下列不是渗出性胸膜炎病因的是（）
A.阻塞性肺炎累及胸膜
B.纵隔肿瘤侵袭胸膜
C.系统性红斑狼疮
D.气胸
E.心力衰竭
参考答案：E
Having an English class, _____.[ ]
A. we heard someone knock at the door
B. someone knocked at the door
C. we heard someone knocked at the door
D. the door was opened
除总进风、总回风外，采区之间应尽量避免角联分支的出现。
