关于加热炉炉膛发生爆炸的原因，下列说法错误的是（）
A、炉膛负压高
B、炉管破裂
C、炉膛产生正压
D、点燃火嘴时，炉膛可燃气体超标
参考答案：A
I just don’t understand ______ that leads to so many teenagers becoming addicted to playing computer games.
A．why it does
B．what it does
C．what it is
D．why it is
耳壳流痰的内治法是（）
A.祛痰散结，活血消肿
B.祛痰散结，疏风活络
C.理气活血，消肿通络
D.理气活血，消肿止痛
E.疏肝理气，祛痰散结
