- 1亦即；也就是
i.e. is a small written sign meaning “that is” or “in other words”. You put it after something a bit wide, then you name the exact thing you mean. The words after i.e. are not a sample pulled from a list; they are the same idea, said more tightly. Bring photo ID, i.e. your passport. It comes from Latin id est, “that is”. People usually write the two letters with full stops (i.e.), and in American style often a after it. You meet it in notes, essays, and forms much more than in friendly talk. When teachers say it aloud, they usually say “that is”, not the letters I-E. Though actually, writers sometimes use i.e. when they only meant “for example”; that is sloppy, not a second meaning.
i.e. 是寫作中的小符號，意思是「也就是」或「換句話說」。它放在比較廣的說法後面，接著說出你真正指的是什麼。後面的內容不是從清單裡挑出來的例子，而是同一個意思說得更精確。格式是「＿＿, i.e. ＿＿」，例如「Bring photo ID, i.e. your passport」，意思是帶上有照片的身分證明，也就是你的護照。
這個縮寫來自拉丁文 id est。寫的時候通常加句點，美式寫法常在後面加逗號。它常見於筆記、論文和表格，比朋友間的談話少見。唸出來的時候，老師通常說 that is，不唸字母。
有些寫作者只是想表示「例如」，也會用它，但那是不夠嚴謹的寫法。它本來的意思仍然是「也就是」。
From the word’s history
From Latin i. e., abbreviation of id est 'that is'.
拉丁文 id est「也就是」的縮寫。
組成From Latin i. e., an abbreviation of id est (“that is”).
原始詞典資料1 筆記錄
以下是外部詞典記錄的用法，摘錄並精簡格式，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。
i.e.adv/ˌaɪˈiː/
- 1
That is, namely, in other words, that is to say.
- While the final episode was made, the show itself was immediately cancelled after the penultimate episode i.e. the final episode never aired.
- [N]o drunkard (i.e.) no Habituall, Impenitent drunkard, ſhall come into Gods Kingdome.
摘錄自 英文維基詞典 English Wiktionary，已精簡格式；依 CC BY-SA 4.0 授權使用，改動後的內容同樣以此授權提供。