Complex sentence: Before the chorus starts Spears jump from the tree in a kind of bungee jump under a water curtain, as Spears land in the stage the first chords from the song starts and the performance keeps going on.
Split into simpler sentences: Before the chorus starts Spears jump from the tree in a kind of bungee jump under a water curtain. As Spears land in the stage, the first chords from the song starts and the performance keeps going on.