It's the last movement that he was working on, but he has a student there, Franz Xaver Suessmayr, and Suessmayr was given instructions and probably sketch pages as to how to finish this.

这是他创作的最后一个乐章,但是莫扎特有一个学生,弗朗兹·克萨韦尔·苏斯迈尔,苏斯迈尔得到了指示,或许还有草稿,把它完成了

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