  In this paper, we give a uniform classification of the generic dual of
quasi-split classical groups, their similitude counterparts, and general spin
groups. As applications, for quasi-split classical groups, we show that the
functorial lifting maps constructed by Cogdell, Kim, Piatetski-Shapiro and
Shahidi are surjective. We also analyze structures of general local Langlands
parameters and explicitly construct a distinguished element for each local
L-packet.
