C大调中没有升半音和降半音。

There are no sharps or flats in the key of C major.

《牛津词典》

这支乐曲不好演奏，到处是升半音、降半音。

It's a difficult piece to play, full of sharps and flats.

《牛津词典》

所有音程也可用减(降半音)或增(升半音)来描述。

All intervals may also be qualified as diminished (a half step or semitone lower), or augmented (a half step or semitone higher).

youdao

So, flats are below, sharps take you up a half step.

降调是下降半音级,而升调是上升半个

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