  In the paper M. Somekawa, {\it{On Milnor $K$-groups attached at semi-Abelian
varieties}}, K-theory, \textbf{4} (1990) p.105, Somekawa conjectures that his
Milnor K-group $K(k,G_1,...,G_r)$ attached to semi-abelian varieties
$G_1$,...,$G_r$ over a field $k$ is isomorphic to ${\rm
Ext}_{\mathcal{M}_k}^r(\mathbb{Z},G_1[-1] \otimes ... \otimes G_r[-1])$ where
$\mathcal{M}_k$ is a certain category of motives over $k$. The purpose of this
note is to give remarks on this conjecture, when we take $\mathcal{M}_k$ as
Voevodsky's category of motives ${\rm DM}^{eff}_{-}(k)$ .
