In 1901, Walter accepted Mahler's invitation to be his assistant at the Court Opera in Vienna.
In 1901 Mahler invited Walter to be his assistant at the Court Opera in Vienna.
In 1901 Mahler invited Walter to be his assistant at the Court Opera in Vienna.
使用更简单的措辞: In 1901, Walter accepted Mahler's invitation to be his assistant at the Court Opera in Vienna. 输出: