Taiwanese is the adjective for Taiwan — it describes anything that belongs to Taiwan or comes from Taiwan: Taiwanese food, a Taiwanese company, Taiwanese films. It is also the noun for a person from Taiwan; one Taiwanese, two Taiwanese (the word does not change, and you can also say 'the Taiwanese' for the people as a whole).

TaiwaneseTaiwanese is the adjective for Taiwan是台灣的形容詞 — it describes anything that belongs to Taiwan or comes from Taiwan用來形容任何屬於台灣、來自台灣的東西: Taiwanese food, a Taiwanese company, Taiwanese filmsTaiwanese food（台灣食物）、a Taiwanese company（一家台灣公司）、Taiwanese films（台灣電影）. It is also the noun for a person from Taiwan它也是台灣人的名詞; one Taiwanese, two Taiwanese (the word does not changeone Taiwanese, two Taiwanese（這個字不會變化）, and you can also say 'the Taiwanese' for the people as a whole你也可以說『the Taiwanese』來指整體台灣人).

Careful here: 'a Taiwanese' sounds a bit odd and a bit cold to many native speakers, the way 'a Chinese' or 'a Japanese' does. Most people say 'a Taiwanese person', 'a Taiwanese student', 'a Taiwanese friend' instead, and that is the safer habit.

Careful here要小心: 'a Taiwanese' sounds a bit odd and a bit cold to many native speakers『a Taiwanese』對很多母語人士來說聽起來有點怪、有點冷淡, the way 'a Chinese' or 'a Japanese' does就像『a Chinese』或『a Japanese』一樣. Most people say 'a Taiwanese person', 'a Taiwanese student', 'a Taiwanese friend' instead大部分人會改說『a Taiwanese person』、『a Taiwanese student』、『a Taiwanese friend』, and that is the safer habit這是比較保險的習慣.

There is a third use that matters a lot at home: Taiwanese is also the name of a language — what people here often call 台語. So 'She speaks Taiwanese' means the language, not just that she is from Taiwan. That is where the word gets slippery, because outside Taiwan many people do not know that language exists, and they may hear 'Taiwanese' and think you mean Mandarin. If it matters, say which one: 'Taiwanese Hokkien' or 'Mandarin'. And in a country with several languages and several peoples — Hakka speakers, Indigenous peoples, families who came in 1949 — the one word 'Taiwanese' is carrying more than one meaning at once.

There is a third use that matters a lot at home還有第三種用法，在台灣本地非常重要: Taiwanese is also the name of a languageTaiwanese也是一種語言的名字 — what people here often call 台語就是這裡的人常說的台語. So 'She speaks Taiwanese' means the language所以『She speaks Taiwanese』意思是她會講台語, not just that she is from Taiwan而不只是她來自台灣. That is where the word gets slippery這就是這個字容易讓人搞混的地方, because outside Taiwan many people do not know that language exists因為台灣以外，很多人根本不知道有這種語言存在, and they may hear 'Taiwanese' and think you mean Mandarin聽到『Taiwanese』可能會以為你指的是國語(Mandarin). If it matters, say which one如果這件事很重要，就講清楚是哪一個: 'Taiwanese Hokkien' or 'Mandarin'『Taiwanese Hokkien』（台語）還是『Mandarin』（國語）. And in a country with several languages and several peoples而且在一個有好幾種語言、好幾群人的國家 — Hakka speakers, Indigenous peoples, families who came in 1949講客語的人、原住民族、1949年來的家庭 — the one word 'Taiwanese' is carrying more than one meaning at once『Taiwanese』這一個字同時背負著不只一種意思.

People argue about it, kindly and unkindly. That argument is part of the word, not a mistake in it.

People argue about it, kindly and unkindly人們會為了這件事爭論，有時候是善意的，有時候不是. That argument is part of the word那個爭論本身就是這個字的一部分, not a mistake in it不是這個字用錯了.

The word is used the same way in daily talk and in formal writing; it is not slang, and it is not stiff. Note the capital T — country words always keep it, even in the middle of a sentence.

The word is used the same way in daily talk and in formal writing這個字在日常對話和正式寫作裡用法是一樣的; it is not slang, and it is not stiff它不是俚語，也不生硬. Note the capital T注意大寫的T — country words always keep it, even in the middle of a sentence國家相關的字永遠要大寫，就算放在句子中間也一樣.