Section_ⅠWelcome to the unit & Reading - Pre­reading

　　　　　　　　　　　　　 [原文呈现] [读文清障]

　　The evolution① of video and sound devices②

　　Early history of TV

　　The first public TV broadcasts were made in the USA in 1925. Later, in 1928, the first long­distance③ TV broadcast was made between the UK and the USA. Regular public broadcasting followed shortly afterwards④， first beginning on 11 May 1928 in New York and on 20 August 1929 in London⑤.

　　Many different people contributed to⑥ the development of TV. Most early TV broadcasts were made using a system developed by John Logie Baird⑦ in the UK. However, his system was very primitive⑧ and had many drawbacks⑨. An American, Philo Farnsworth, made important breakthroughs⑩ in the development⑪ of TV in the late 1920s⑫ and early 1930s. Modern TVs use many of the principles⑬ first discovered by Farnsworth.

　　John Logie Baird constructed⑭ the first colour TV in 1928, but it was not until 1938 that the first colour TV programme was broadcast⑮. It took more than two decades, though, until 1951, for regular colour TV broadcasts to begin in the USA. Regular colour TV broadcasts were delayed⑯ in the UK until 1967. However, within a short time nearly all TV broadcasts were made in colour, and within five years more colour TVs than black­and­white⑰ TVs were being used. ①evolution/ˌiːvə'luːʃn/ n．演变，发展；进化

　with the evolution of 随着......的演变

②device/dI'vaIs/ n．装置，设备

③long­distance是由"形容词＋名词"构成的合成形容词，在句中通常作定语，意思是"远距离的；长途的"。

④afterwards adv.以后，后来

⑤现在分词短语beginning on ...作伴随状语。

⑥contribute to贡献，捐献；有助于

　make contributions to对......做贡献

⑦现在分词短语using a system developed by ...在句中作方式状语；其中过去分词短语developed by ...作a system的后置定语。

⑧primitive adj.原始的，远古的

⑨drawback/'drɔːbæk/ n．缺点，缺陷；不利条件

⑩make breakthroughs取得突破

⑪development n．开发，研制；发展

⑫in the late 1920s在20世纪20年代末期

⑬principle/'prInsəpl/ n．原理，法则；道德原则，行为准则

⑭construct/kən'strʌkt/ vt.制造；修筑，建造

⑮本句为强调句型，在此强调时间状语not until 1938。

⑯delay/dI'leI/ vt.& vi.(使)推迟，延迟n.延误，延迟

⑰black­and­white/ˌblækən'waIt/ adj.黑白的