空温式汽化器包含蒸发部与加热部，蒸发部由端板管连接并排的导热管构成，加热部由用弯管接头串联成 一体的导热管组成。
参考答案：对
Hello, I _______ you ______ in London. How long have you been here?
A．don’t know; were
B．hadn’t known; are
C．haven’t known; are
D．didn’t know ; were
肛门突然出现暗紫色痛性肿块的是（）
A.肛周脓肿
B.混合痔
C.血栓性外痔
D.肛裂
E.肛瘘
