The movement of the working fluid causes the center of gravity of the bird to change and it dips the beak into a glass of water and the fluid 
(The movement of the working fluid; causes; the center of gravity of the bird) (it; dips; the beak; into a glass of water and the fluid)
The movement of the working fluid it
causes dips
the center of gravity of the bird
the beak into a glass of water and the fluid