Central heating was present in every upper-and middle-class home by the second half of the 19th century.
出自-2014年6月阅读原文
The heating system doesn't work.
出自-2013年6月听力原文
In another firm the workers were constantly complaining about the malfunctioning heating system, but the owners was too busy or too mean to do anything about it.
出自-2011年6月听力原文