Complex sentence: Her career in crossword puzzles began at the "New York World" in 1920; although she had been hired as the publisher's secretary, she was told to assist crossword inventor Arthur Wynne in proofreading puzzles prior to publication.
Split into simpler sentences: Her career in crossword puzzles began at the "New York World" in 1920. Although she had been hired as the publisher's secretary, she was told to assist crossword inventor Arthur Wynne in proofreading puzzles prior to publication.