锅炉附件包括安全门、水位计、吹灰器、热工仪表、自动控制装置等。
参考答案：错
传播疾病最严重的医学昆虫是
A．蝇
B．蚊
C．蟑螂
D．蚤
E．虱
We don’t have much homework now and our school-bags are _____ they used to be. [ ]
A. as heavy as
B. as heavily as
C. not as heavily as
D. not so heavy as
