The adverb: without meaning to. It attaches to the action rather than the result — "I unintentionally left her out", "the film is unintentionally hilarious", "he unintentionally revealed the ending".

The adverb這個副詞：without meaning to意思是「不是故意的」。It它 attaches to the action rather than the result附著在動作上而不是結果上——"I unintentionally left her out"「我不小心把她漏掉了」、"the film is unintentionally hilarious"「這部片子不小心變得很好笑」、"he unintentionally revealed the ending"「他不小心透露了結局」。

In real speech, the shorter *by accident*, *by mistake*, or *I didn't mean to* is far more common; *unintentionally* is the written and slightly formal option, and it is the one you see in reports, notices, and public apologies.

In real speech在真正的口語裡，the shorter *by accident*, *by mistake*, or *I didn't mean to*比較短的 by accident、by mistake，或 I didn't mean to is far more common更常用；*unintentionally*而 unintentionally is the written and slightly formal option是書面、稍微正式一點的選項，and it而它 is the one you see in reports, notices, and public apologies就是你會在報告、公告、公開道歉裡看到的那個字。

It also has a favourite construction of its own: unintentionally + adjective, where something achieves an effect it never aimed at — unintentionally funny, unintentionally rude, unintentionally cruel. That pattern is so common in reviews and comments that it is worth learning as a unit.

It它 also has a favourite construction of its own還有一個自己偏好的句型：unintentionally + adjective也就是 unintentionally 加形容詞，where something achieves an effect it never aimed at指某件事達成了一個它本來沒打算要的效果——unintentionally funny不小心很好笑、unintentionally rude不小心很沒禮貌、unintentionally cruel不小心很殘忍。That pattern這個句型 is so common in reviews and comments在評論和留言裡很常見 that it is worth learning as a unit值得把它整組學起來。

Placement is flexible: before the verb ("she unintentionally offended him") or at the end ("she offended him unintentionally"), with the end position giving the word slightly more weight.

Placement位置 is flexible很靈活：before the verb可以放在動詞前面（"she unintentionally offended him"「她不小心冒犯了他」） or at the end或放在句尾（"she offended him unintentionally"「她冒犯了他，不是故意的」），with the end position giving the word slightly more weight而放在句尾會讓這個字的語氣稍微重一點。