In, from, or facing the southwest part of somewhere. It is an adjective, so it sits in front of a noun: the southwestern coast, a southwestern accent, southwestern France.

In, from, or facing在、來自，或面向 the southwest part of somewhere某個地方的西南部。It is an adjective這是個形容詞， so it sits in front of a noun所以放在名詞前面： the southwestern coast, a southwestern accent, southwestern France像the southwestern coast（西南海岸）、a southwestern accent（西南口音）、southwestern France（法國西南部）。

Two things are worth separating. First, southwestern usually describes a REGION of a larger place — "southwestern Taiwan" means the bottom-left part of Taiwan, not a place to the southwest of Taiwan. If you mean a place lying outside and to the southwest, people normally say "southwest of Taiwan".

Two things are worth separating有兩件事值得分清楚。First第一， southwestern usually describes a REGION of a larger place southwestern通常是在講一個更大地方裡面的「一個區域」— "southwestern Taiwan" means the bottom-left part of Taiwan「southwestern Taiwan台灣西南部」指的是台灣左下角那一帶， not a place to the southwest of Taiwan不是台灣西南方外面的另一個地方。If you mean a place lying outside and to the southwest如果你指的是在外面、位於西南方的地方， people normally say "southwest of Taiwan"通常會說「southwest of Taiwan台灣的西南方」。

Second, in American English "Southwestern" with a capital letter often means one specific region — Arizona, New Mexico, and nearby — and carries a whole flavour with it: desert, adobe houses, Mexican-influenced food, warm earth colours. A menu saying "Southwestern chicken" is promising you that style, not telling you a direction.

Second第二， in American English "Southwestern" with a capital letter美式英語裡大寫的Southwestern often means one specific region常常指一個特定的地區— Arizona, New Mexico, and nearby亞利桑那、新墨西哥附近一帶— and carries a whole flavour with it還帶著一整套風格： desert, adobe houses, Mexican-influenced food, warm earth colours沙漠、土磚房、帶墨西哥風味的食物、溫暖的大地色系。A menu saying "Southwestern chicken"菜單上寫「Southwestern chicken西南風味雞肉」， is promising you that style是在跟你保證那種風格， not telling you a direction不是在告訴你方向。

In writing about weather and geography this word is everywhere; in casual conversation people usually just say "the southwest" and skip the adjective.

In writing about weather and geography在講天氣或地理的文章裡， this word is everywhere這個字到處都是； in casual conversation平常講話的時候， people usually just say "the southwest"大家通常直接說「the southwest西南部」， and skip the adjective省略掉這個形容詞。