with parallel mean curvature vector field and codimesion 2. We obtain some sufficient and
necessary conditions for such submanifolds to be conservative. In particular, we obtain a
complete classification of 3-dimensional biconservative submanifolds in S^ 4 * RS 4× R and
H^ 4 * RH 4× R with nonzero parallel mean curvature vector field. We also get some results
for biharmonic submanifolds in S^ n * RS n× R and H^ n * RH n× R.