  A simple 1D lattice gas model is presented, which very well describes the
equilibrium and kinetic behaviors of water confined in a thin carbon nanotube
found in an atomistic molecular dynamics(MD) simulation {[} Nature {\bf 414},
188 (2001) {]}. The model parameters are corresponding to various physical
interactions and can be calculated or estimated in statistic mechanics. The
roles of every interaction in the water filling, emptying and transporting
processes are clearly understood. Our results indicate that the physical
picture of the single-file kinetics is very simple.
