A semitone is the smallest step you usually use in Western piano music: the pitch gap between two keys that sit next to each other, black or white. From C to C-sharp is a semitone; from E to F — no black key in between — is also a semitone. Twelve semitones make an octave.

A semitone is是 in Western piano music在西方鋼琴音樂裡 you usually use你最常用到的 the smallest step最小音程： the pitch gap也就是音高差距， between two keys發生在兩個琴鍵之間， that sit next to each other彼此相鄰、 black or white不分黑鍵白鍵。 From C to C-sharp從C到C-sharp is a semitone是一個半音； from E to F從E到F no black key in between——中間沒有黑鍵—— is also a semitone也是一個半音。 Twelve semitones十二個半音 make an octave構成一個八度。

British teachers say semitone; Americans often say half step or half-tone. A whole tone (sometimes just called a tone in this music sense) is two semitones.

British teachers say semitone英式老師會說semitone； Americans often say美式常說 half step or half-tonehalf step或half-tone。 A whole tone一個全音 sometimes just called a tone in this music sense（在這個音樂用法裡有時直接叫做tone） is等於 two semitones兩個半音。

Though actually, singers and violin players can slide through pitches smaller than a semitone, but the piano, and most pop harmony, is built on this half-step grid. The word is at home in lessons, exams, and choir practice, not in ordinary chat about “tone of voice.”

Though actually不過其實， singers and violin players歌手和小提琴手 can slide through可以滑過 smaller than a semitone比半音更小的 pitches音高， but但 the piano, and most pop harmony鋼琴和大多數流行和聲， is built on都是建立在 this half-step grid這個半音音階上的。 The word is at home這個字常出現 in lessons, exams, and choir practice在課堂、考試和合唱練習裡， not不是 in ordinary chat about "tone of voice"出現在講「tone of voice」的日常閒聊裡。