  We investigate the structure of gapless edge modes propagating at the
boundary of some fractional quantum Hall states. We show how to deduce explicit
trial wavefunctions from the knowledge of the effective theory governing the
edge modes. In general quantum Hall states have many edge states. Here we
discuss the case of fractions having only two such modes. The case of
spin-polarized and spin-singlet states at filling fraction 2/5 is considered.
We give an explicit description of the decoupled charged and neutral modes.
Then we discuss the situation involving negative flux acting on the composite
fermions. This happens notably for the filling factor 2/3 which supports two
counterpropagating modes. Microscopic wavefunctions for spin-polarized and
spin-singlet states at this filling factor are given. Finally we present an
analysis of the edge structure of a non-Abelian state involving also negative
flux. Counterpropagating modes involve in all cases explicit derivative
operators diminishing the angular momentum of the system.
