英文的preposition (前置詞 或 介詞)是表示出主體 (subject) 和客體 (object) 之間的關係。如:
· The key is in the box.
鑰匙就是主體,盒子是客體。
Preposition 可以連同 relative pronoun 合用而形成更長的句子,例如:
· This is the box in which I put the key.
(中):這是我放進鑰匙的盒子。
· The athlete jumped over where he fell in the previous attempt.
(中):那健兒跳越他上次嘗試中跌倒的地方。
有時這些字後面沒有一個客體,我們就不當它是preposition 而是一個形容動詞 (adverb) 或形容詞(adjective),如:
· Please come in.
(中):請進來。(“in” 是 adverb)
· The bet is on.
(中):打賭開始了。(“on” 是adjective)
· He came across as a nice guy.
(中):他看似好人。(“across” 是 adverb)
· It is easy to start a project, but it is not easy to see it through.
(中):開始計劃時容易,但要完成可就不容易了。
(“through” 是adverb)
· Those who agree please stand up.
(中):同意的人請站起來。(“up” 是adverb)
· Their relationship is over.
(中):他們的關係完結了。(“over” 是adjective)
· Why don’t you put the cat out?
(中):為什麽你不放了貓兒出去呢?(“out” 是adverb)