It SOUNDS like George is singing "worrying on a dark race horse", but immediately before that line he said "I'm a dark horse", so saying "a dark race horse" in the very next line would be redundant, and besides that, it didn't make sense to have one horse riding another horse, so I checked lirama.net and found the correct lyrics, However, it STILL sounds like whatever George is saying instead of "worrying", is three syllables, as in "hurrying", rather than two, as in the allegedly correct "running".