By Tom Burridge, BBC News

媒體英語會帶大家一起學習BBC撰稿人在報道世界大事時常用到的單詞和短語。

Background: IBM超級電腦“沃森”(Watson) 擊敗了美國《危險邊緣》節目歷史上最成功的兩位選手。被擊敗的兩位選手其中一位在此之前是連贏74場比賽的紀錄保持者。

Jeopardy is one of America's oldest and most popular quiz shows. But this time, inside the brightly-lit studio, a contest billed as 'man versus machine' - the programme's producers pitted two of their most successful contestants ever against a computer. Known as Watson, the computer is a giant piece of hardware, equivalent in size to several fridges. And over three programmes, Watson beat his human contenders with ease.

In a split-second, Watson is able to digest the question and try and match it against huge amounts of information it has at its disposal. It very quickly assesses how good a match it thinks it has and buzzes either very quickly, or not so quickly, reflecting how confident it is that it has the right answer.

Watson is also able to notice nuances in language, between say 'bat' the animal and 'bat' used in sports. On a prime-time US TV show with millions of viewers it was great publicity for IBM. But the company says Watson the computer is an IT genius and a breakthrough in computing.