  Trial wavefunctions, constructed explicitly from the unique 2-dimensional
Mott insulating state with antiferromagnetic order, are proposed to describe
the low-energy states of a Mott insulator slightly doped with holes or
electrons. With the state behaving like charged quasi-particles with
well-defined momenta, a rigid band is observed. These states have much less
pairing correlations than previously studied ones. Small Fermi patches obtained
are consistent with recent experiments on high Tc cuprates doped lightly with
holes or electrons. States showing the incoherent and spin-bag behaviors are
also discussed. Using these wavefunctions, a number of results obtained by
exact calculations are reproduced.

Strongly Correlated Electrons