  Based on a variational approach, we propose that there are two kinds of low
energy states in the t-J type models at low doping. In a quasi-particle state
an unpaired spin bound to a hole with a well-defined momentum can be excited
with spin waves. The resulting state shows a suppression of antiferromagnetic
order around the hole with the profile of a {\em spin bag}. These spin-bag
states with spin and charge or hole separated form a continuum of low-energy
excitations. Very different properties predicted by these two kinds of states
explain a number of anomalous results observed in the exact diagonalization
studies on small clusters up to 32 sites.
