  Let $K$ be a field, and $A=K[a_1,\ldots ,a_n]$ a solvable polynomial algebra
in the sense of [K-RW, {\it J. Symbolic Comput.}, 9(1990), 1--26]. It is shown
that if $A$ is an $\mathbb{N}$-graded algebra of $({\cal B},d(~))$-type, then
$A$ has a graded monomial ordering $\prec_{gr}$. It is also shown that $A$ is
an $\mathbb{N}$-filtered algebra of $({\cal B},d(~))$-type if and only if $A$
has a graded momomial ordering, where ${\cal B}$ is the PBW basis of $A$.
