可引起金属音调咳嗽的是（）
A.百日咳
B.急性肺水肿
C.支气管扩张
D.主动脉瘤
E.胸膜炎
参考答案：D
Most men don't cry ______, but they sometimes cry when they are alone.[ ]
A. in public
B. on purpose
C. by accident
D. in peace
脉冲点火灶在点火时常见故障和产生原因有哪些？如何排除？
