Applied chords serve a dominant function (V, V7, viio, viio7), and function as a temporary key center, rather than a new home key. Put differently, an applied chord is a dominant chord borrowed from another key. Accidentals outside of the key signature are an indication that an applied chord is present. Applied chords are notated with a slash. The chord to the left of the slash is the function of the applied chord, and the chord to the right of the slash is the chord being tonicized.

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