"When I was a boy, my father, a baker, introduced me to the wonders of song," tenor Luciano Pavarotti relates. "He urged me to work very hard to develop my voice. Arrigo Pola, a professional tenor in my hometown of Modena, Italy, took me as a pupil. I also enrolled in a teachers college. On graduating, I asked my father, &ls;Shall I be a teacher or a singer?' "&ls;Luciano,' my father replied, &ls;if you try to sit on two chairs, you will fall between them. For life, you must choose one chair.' "I chose one. It took seven years of study and frustration before I made my first professional appearance. It took another seven to reach the Metropolitan Opera. And now I think whether it's laying bricks, writing a book&md;whatever we choose&md;we should give ourselves to it. Commitment, that's the key. Choose one chair."