Đáp án:

1. When he was 30, he started to become a well-known composer, and he wrote heroic works about struggle and revolution 

2. In his late 20s, he started losing his hearing, and he became quite ill during the last years of his life, and died at the age of 57 in Vienna 

3  Beethoven composed many symphonies, well-known piano sonatas, and became the master composer of all time

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1. When he was 30, he started to become a well-known composer, and he wrote heroic works about struggle and revolution.

2. In his late 20s, he started losing his hearing, and he became quite ill during the last years of his life, and died at the age of 57 in Vienna.

3. Beethoven composed many symphonies, well-known piano sonatas, and became the master composer of all time.