In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
Q: Passage: Handel's Hamburg years provided him with a composing apprenticeship, particularly although not exclusively as a writer of opera. The influence of Keiser, which began during this period, was  significant throughout Handel's  career. Apart from his lifelong habit of "borrowing" fragments from Keiser's operas for use in his own works, he adopted and retained many of his mentor's compositional characteristics; according to Hicks, "[Handel] never relinquished French forms for overtures and dance music, and his use of orchestral colour, particularly the occasional instrumental doubling of the voice colla parte, was derived from German models".The loss of much of Handel's early work was first noted by his earliest biographer, Mainwaring (1760), who refers to "a great quantity of music" from Hamburg and Italy, adding that it was not known  how much of it still existed. On departing from Hamburg, Handel spent a further three years in Italy before settling in London, where he remained the dominant composer of Italianate opera for the following thirty years. After his Hamburg initiation, Handel composed more than forty operas, beginning with Rodrigo  in 1707, and ending in 1740 with Deidamia. These works were quickly forgotten after Handel's death; modern revivals did not begin until the 1920s. Dean and Knapp believe that, despite the years of relative neglect, Handel's achievements as a composer of opera entitle him to rank alongside Monteverdi, Mozart, Verdi, and Richard Wagner as one of the supreme masters of the genre.
A:
What is the name of the person who adopted and retained many of his mentor's compositional characteristics?