  The recent Investigations in the chiral quark model show that kaon
productions of nucleon play an important role in understanding the structure of
baryons. The evidences of a third $S_{11}$ resonance in the second resonance
region and two narrow states around 2 GeV suggest a set of the molecular type
baryons with hidden strangeness. Confirming these states requires further
theoretical and experimental studies of the strangeness production.
