You might hum the tune, but you sing the words, and for at least one generation the words were Hal David's, the songwriter in one of the great composer-lyricist collaborations of the 20th century, who died on Saturday. Hal David wrote phrases that skewered the heart of the lovestruck teenager, especially when interpreted by Dionne Warwick, words that pumped tragedy into the breakup and resolve into the determination to milk every minute of it. What do you get when you fall in love, he asked. You get enough germs to catch pneumonia, he answered. After you do he'll never phone ya. He hitched the eternal to the everyday and made both seem credible. But he wasn't only the laureate of the lovesick. With Burt Bacharach, world peace, global harmony and the grit behind the glamour were merged in words and music. It was about believability, simplicity and emotional impact, David said, and the hardest of these was simplicity.