照应关系
照应(Reference)指用代词等语法手段表示的语义关系。英语中的照应分为3类：人称照应、指示照应和比较照应。其中较难的是分句照应 (ClausalReference)。分句照应指的是某些词语的所指对象不是词或者短语，而是分句、句子、句子组合，甚至一个完整的语篇。可以用做分句照应的词语分为以下3类。
(1)here，it，this等词汇既可用于前照应，又可用于后照应。
(2)that，(the)above，the foregoing等只用于前照应。
(3)as follows，the following，below，thus等仅用于后照应。
这一语言现象常常是命题点。
Example:
It looks as if it came straight from the set of Star Wars. It hasfour-wheel drive and rises above rocky surfaces. It lowers and raises its nosewhen going up and down hills. And when it comes to a river, it turns amphibious:two hydrojets power it along by blasting water under its body. There is room fortwo passengers and a driver, who sit inside a glass bubble operating electronic,aircraft-type controls. A vehicle so daring on land and water needs windscreenwipers—but it doesn’t have any. Water molecules are disintegrated on thescreen’s surface by ultrasonic sensors.