2．不定式、動(dòng)名詞和分詞作表語的區(qū)別 
　 (1)不定式作表語 
　 1)不定式作表語一般表示具體動(dòng)作，特別是表示將來的動(dòng)作。 
　 To do two things at a time is to do neither．--次做兩件事等于未做。 
　 What I would suggest is to start work at once.我的建議是立刻開始干。 
　 2)如果主語是不定式（表示條件），表語也是不定式（表示結(jié)果）。 
　 To see is to believe.百聞不如一見。 
　 To work means to earn a living．工作就是為了生活。 
　 3)如果主語是以aim，duty，hope，idea，happiness，job，plan，problem，purpose，thing，wish等為中心的名詞，或以what引導(dǎo)的名詞性從句，不定式作表語是對(duì)主語起補(bǔ)充說明作用。 
　 His wish is to buy a luxurious car in the near future．他的希望是在不遠(yuǎn)的將來買一輛豪華轎車。 
　 The function of Louis Sullivan’s architecture was to provide large uninterrupted floor areas and to allow ample light into the interior. 
　 The most important thing is to negotiate with them about the future of the plant.
　 (2)動(dòng)名詞作表語：動(dòng)名詞作表語，表示抽象的一般性的行為。 
　 Our work is serving the people．我們的工作是為人民服務(wù)。 
　 His hobby is collecting stamps．他的愛好是集郵。 
　 (注)動(dòng)名詞作表語時(shí)與進(jìn)行時(shí)態(tài)中的現(xiàn)在分詞形式相同，但其所屬結(jié)構(gòu)迥異，進(jìn)行時(shí)態(tài)說明動(dòng)作是由主語完成的。動(dòng)名詞做表語，說明主語的性質(zhì)或情況。 
　 People cannot but feel puzzled，for they simply cannot understand how he could have made such a stupid mistake. 
　 His victory in the final was no more convincing than I had expected.
　 (3)分詞作表語 
　 分詞做表語有兩種情況，一種是現(xiàn)在分詞做表語，一種是過去分詞做表語，這兩者區(qū)別是考試中經(jīng)常考到的地方。一般來說，表示心理狀態(tài)的動(dòng)詞如excite，interest等都是及物動(dòng)詞，漢語意思不是“激動(dòng)”，“高興”，而是“使激動(dòng)”、“使高興”，因而現(xiàn)在分詞應(yīng)該是“令人激動(dòng)的”、“令人高興的”，過去分詞則是“感到激動(dòng)的”和“感到高興的”。所以，凡表示“令人……的”都是-ing形式，凡是表示“感到……”都用-ed形式。換句話說，若人對(duì)……感興趣，就是somebody is interested in...,若人/物本身有興趣時(shí)，就是說sb./sth. is interesting.這類詞常見的有： 
　 interesting使人感到高興--interested感到高興的 
　 exciting令人激動(dòng)的--excited感到激動(dòng)的 
　 delighting令人高興的--delighted感到高興的 
　 disappointing令人失望的--disappointed感到失望的 
　 encouraging令人鼓舞的--encouraged感到鼓舞的 
　 pleasing令人愉快的--pleased感到愉快的 
　 puzzling令人費(fèi)解的--puzzled感到費(fèi)解的 
　 satisfying令人滿意的---satisfied感到滿意的 
　 surprising令人驚異的--surprised感到驚異的 
　 worrying令人擔(dān)心的--worried感到擔(dān)心的 
　 Travelling is interesting but tiring．旅行是有趣的，但是使人疲勞。 
　 The pupils will get confused if they are made to learn too much．如果要學(xué)生學(xué)得太多，他們會(huì)感到糊涂的。 
　 The argument is very convincing．他的論點(diǎn)很令人信服。 
　 They were very excited at the news．聽到這個(gè)消息，他們非常激動(dòng)。