And we may find a clue in several survived manuscripts of solfeggio and esercizi. I will try to read a characteristic of singing by Constanze from these exercises which are considered to have been written occasionally. Because Mozart used this paper during 1781-87 years, we may admit the hypothesis that Mozart wrote this piece in 1782, particularly after the date of marriage, August 4, 1782.
Unfinished shape is clear because full spaces are remaining.
Because I can't think that Constanze sang the sequel impromptu, only a part of C major key would be used practically. A musical scale of wave shape with 8th notes and 16th notes make 2 measures, 4measures and 5 measures groups increasingly and are risen successively. As soon as it reaches the highest note 'b2' after the continuous rising musical scale with trills, it leaps down to notes 'b' and 'a'. Several confirmations of the highest tone 'b2' bring ending passing through D major and G major. We may say that this piece is easier than other etudes as exercise concerning both height of voices and degree of difficulty.