  Bosonized q-vertex operators related to the 4-dimensional evaluation modules
of the quantum affine superalgebra $U_q[\hat{sl(2|1)}]$ are constructed for
arbitrary level $k=\alpha$, where $\alpha\neq 0, -1$ is a complex parameter
appearing in the 4-dimensional evaluation representations. They are
intertwiners among the level-$\alpha$ highest weight Fock-Wakimoto modules.
Screen currents which commute with the action of $U_q[\hat{sl(2|1)}]$ up to
total differences are presented. Integral formulae for N-point functions of
type I and type II q-vertex operators are proposed.
