They pump blood to the lower chambers, the right and left ventricles, which are the main pumps of the heart.
(They; pump; blood; to the lower chambers) (They; left; ventricles, which are the main pumps of the heart) (ventricles; are; the main pumps of the heart)
They They ventricles
pump left are
blood to the lower chambers
ventricles, which are the main pumps of the heart
the main pumps of the heart