Complex sentence: The opening track is based almost entirely on a tritone interval played at slow tempo on the electric guitar, and the song's lyrics concern a "figure in black" which bassist Geezer Butler claims to have seen after waking up from a nightmare.
Split into simpler sentences: The opening track is based almost entirely on a tritone interval played at slow tempo on the electric guitar. The song's lyric concerns a "figure in black" which bassist Geezer Butler claims to have seen after waking up from a nightmare.