  We study a one-dimensional Bose system with repulsive delta-function
interaction in the presence of an SU(2) intrinsic degree of freedom on the
basis of the coordinate Bethe-ansatz. The ground state and the low-lying
excitations are determined by both numerical and analytical methods. It is
shown that the ground state is an isospin-ferromagnetic state, and the
excitations are composed of three elementary particles: holons, antiholons, and
isospinons. The isospinon is a triplet coupled to the "ferromagnetic"
background anti-parallelly.
