急性左心衰竭表现为
A．面色发红
B．呼吸频率增快
C．咳大量脓痰
D．端坐位
E．突发呼吸困难
参考答案：B,D,E
— Hi, what did our monitor say just now?
— Every boy and every girl as well as teachers who are to visit Water Cube ______ asked to be at school gate before 6∶30 tomorrow morning.
A．is
B．were
C．are
D．was
炉膛结焦的原因是什么？
