Following up Harald's point (and then I'm gong to stop, honest), It's usually the way with "art" songs that the lyric isn't usually the most important element of the song; it is a vehicle for the voice, which is considered as another instrument. Folk song, generally speaking, is a form of story-telling: the content of the lyric is the most important element, and would still work if you recited the words instead of singing them. You can often find extra syllables in a song, where the tune is alterd or extended to fit. The Blacksmith has an example: I fear the scorching sun may shine and burn his beauty ... In conventional (what a wonderful undertone of sneering and condecension in that word!) music, the extra bit would be dropped: look what happens when a poem that doesn't scan too well (and why should it?). Can't think of an example!

Ok, lecture over!

Steve