  We investigate analytic solutions to Witten's bosonic string field theory and
Berkovits' WZW-type superstring field theory. We construct solutions with
parameters out of simpler ones, using a commutative monoid that includes the
family of wedge states. Our solutions are generalizations of solutions for
marginal deformations by nonsingular currents, and can also reproduce Schnabl's
tachyon vacuum solution in bosonic string field theory. This implies that such
known solutions are generated from simple solutions which are based on the
identity state. We also discuss gauge transformations and induced field
redefinitions for our solutions in both bosonic and super string field theory.
