冬季应做好设备和管道的保温防冻工作，要特别注意溢流管、防爆装置的防冻。
参考答案：对
— How do you usually find out about new software?
— In the magazines like Popular Electronics. That's _____ computer companies usually advertise. [ ]
A. which
B. where
C. what
D. why
控制通气包括（）和（）。
