发生露点腐蚀时，是由于（）凝结在低温受热面上，从而发生腐蚀。
A、硫
B、硫酸
C、硫化氢
D、连多硫酸
参考答案：B
施工总承包企业的资质按专业类别共分为（）个资质类别。
A.8
B.10
C.t2
D.15
—Are you going to the football game this weekend?
—Probably not. The tickets are __________ for me.
A．terrible expensive
B．so much expensive
C．far too expensive
D．highly expensive
