3L英語(yǔ)第四冊(cè)lesson 17

[ti:] [ar:] [al:] [by:] [00:02.00]喜歡tingclass.net，就把tingclass.net復(fù)制到QQ個(gè)人資料中！Lesson 17 [00:03.70]第17課 [00:05.40]Television Day:Computers [00:07.56]電視日:計(jì)算機(jī) [00:09.73]"...the astronauts are returning to earth at exactly 5.24." [00:12.50]...宇航員將于5:24整回到地球, [00:15.27]Splash-down will be in the Pacific,427 miles west of Hawaii. [00:18.60]"并將在位于夏威夷西部427英里的太平洋海面上濺落." [00:21.93]You have often heard announcements like this on television. [00:24.36]你常會(huì)從電視聽(tīng)到上述的預(yù)告. [00:26.79]Scientists can tell us exactly [00:28.81]舉例說(shuō),科學(xué)家能準(zhǔn)確地告訴我們 [00:30.84]when a space-capsule will arrive on the moon for instance, [00:33.32]宇宙密封小艙何時(shí)抵達(dá)月球 [00:35.80]and exactly when it will return. [00:37.83]和何時(shí)返回. [00:39.85]They can calculate things like this to the nearest second. [00:42.42]對(duì)這類(lèi)事情,他們的計(jì)算可精確至秒. [00:45.00]How do they do it? [00:46.38]他們是如何做的呢? [00:47.77]Well,of course,they use mathematics. [00:49.99]當(dāng)然他們運(yùn)用了數(shù)學(xué). [00:52.21]We can all do simple sums on paper, [00:54.39]我們都能在紙上做簡(jiǎn)單的算術(shù)題, [00:56.57]but we must use computers for extremely difficult calculations. [00:59.55]但必須用計(jì)算機(jī)進(jìn)行復(fù)雜的運(yùn)算. [01:02.53]Perhaps you have seen mechanical calculating-machines in banks and offices. [01:05.61]你也許在銀行和辦公室見(jiàn)過(guò)機(jī)械計(jì)算機(jī). [01:08.69]They can work very quickly,but nothing like computers. [01:11.37]盡管它們運(yùn)算迅速,但與電子計(jì)算機(jī)截然不同. [01:14.05]Computers aren't mechanical. [01:15.91]電子計(jì)算機(jī)不是機(jī)械的. [01:17.78]They don't have wheels and gears in them. [01:19.96]它們沒(méi)有轉(zhuǎn)輪和齒輪. [01:22.14]Instead,they work on electrical circuits [01:24.57]而是通過(guò)電路工作的, [01:27.00]and can do difficult calculations at tremendous speed. [01:29.63]可以迅速進(jìn)行復(fù)雜的運(yùn)算 [01:32.25]They can work 100 million times faster than the human mind! [01:35.73]它們運(yùn)算速度要比人腦快上一億倍.

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