A set of three books, films, plays or games that belong together — same world, same people, or one story told across three parts. The Lord of the Rings is a trilogy; so is the first Star Wars set. The word says something more than 'three': it says the three were meant to go together, and that reading or watching all three gives you something one alone cannot.

A set of three books, films, plays or games一套三本的書、三部電影、三齣戲或三款遊戲 that belong together彼此有關聯 — same world同一個世界，same people同一群人物，or one story told across three parts或是一個故事分成三個部分來說。 The Lord of the Rings《魔戒》 is是 a trilogy一部三部曲；so is the first Star Wars set最早那一套《星際大戰》也是。 The word這個字 says something more than 'three'說的比「三」還多：it says the three were meant to go together它是說這三個本來就該放在一起，and that reading or watching all three gives you something one alone cannot而且把三個都讀完或看完會得到單獨一個給不了的東西。

Though actually, the writer does not always plan it. Plenty of trilogies happen by accident — a book sells well, a second follows, a third finishes it off, and the publisher prints 'The X Trilogy' on the box afterwards. And once a fourth part arrives, English has no comfortable word for it, so people either keep saying trilogy out of habit or joke about it.

Though actually不過其實，the writer作者 does not always plan it不一定一開始就有規劃。 Plenty of trilogies happen by accident很多三部曲其實是意外形成的 — a book sells well一本書賣得好，a second follows第二本就跟著出，a third finishes it off第三本收尾，and the publisher prints 'The X Trilogy' on the box afterwards然後出版社才在封面印上「The X Trilogy」。 And once a fourth part arrives而一旦第四部出現，English has no comfortable word for it英文沒有一個順口的字可以講它，so people either keep saying trilogy out of habit or joke about it所以人們要嘛出於習慣還是說 trilogy，要嘛就拿這件事開玩笑。

It is a countable noun: a trilogy, two trilogies (note the y turns to ies). You say a trilogy of novels, or the Godfather trilogy.

It它 is是 a countable noun一個可數名詞：a trilogy, two trilogies a trilogy，two trilogies (note the y turns to ies)（注意 y 要變成 ies）。 You你 say a trilogy of novels會說 a trilogy of novels，or the Godfather trilogy或 the Godfather trilogy。

The word came into English from Greek theatre, where three tragedies were performed one after another at a festival, and it still carries a slightly literary, respectful tone — you would not usually call three random sequels a trilogy unless they really hang together.

The word這個字 came into English from Greek theatre從希臘戲劇進入英文，where three tragedies were performed one after another at a festival當時在慶典上會連續演出三齣悲劇，and it still carries a slightly literary, respectful tone而它到現在還帶著一點文學、慎重的味道 — you would not usually call three random sequels a trilogy unless they really hang together除非三部作品真的緊密相關，不然你通常不會隨便把三部續集叫做 trilogy。