First listen and then answer the question.
Has Big Ben ever gone wrong?
When you visit London, one of the first things you will see is Big Ben, the famous clock which can be heard all over the world on the B. B. C. If the Houses of Parliament had not been burned down in1834,the great clock would never have been erected. Big Ben takes its name from sir Benjamin Hall who was responsible for them making of the clock when the new Houses of Parliament were being built. It is not only of immense size, but is extremely accurate as well. Officials from Gfeenwich Observatory have the clock checked twicea day. On the B. B. C. you can hear the clock when it is actually striking because microphones are connected to the clock tower. Big Ben has rarely gone wrong. Once, however, it failed to give the correct time. A painter who had been working on the tower hung a pot of paint on one of the hands and slowed it down!New words and expressions 生词和短语
parliament(1.3)/'pɑ:ləmənt/ n. 议会，国会
observatory (1.8) /əb'zə:vətəri/n.天文台
accurate(1.7)/'ækjvrət/ adj. 准确的
microphone (1.9)/'maikrəfəvn/ n.扩音器，麦克风
Notes on the text 课文注释
1 Big Ben,大钟的名字，译成“大本”。
2 the B.B.C.是英国广播公司(British Broadcasting Corporation)的缩写。
3 If the Houses of Parliament had not been burned down in 1834,the great clock would never have been erected.如果不是国会大厦在1834年被焚毁的话，这座大钟永远也不会建造。这是一个表示与过去事实不相符的虚拟语气结构。
4 take its name from,以……命名。
5 when the new Houses of Parliament were being built,注意这个从句中过去进行时的被动结构。
6 It is not only of immense size,它不仅外型巨大，“to be of+名词”用来表示人或物的特征。
7 Big Ben has rarely gone wrong.“大本”钟很少出差错。