  We investigate the dynamics of a pair of short laser pulse trains propagating
in a medium consisting of three-level $\Lambda$-type atoms by numerically
solving the Maxwell-Schr\"odinger equations for atoms and fields. By performing
propagation calculations with different parameters, under conditions of
electromagnetically induced transparency, we compare the propagation dynamics
by a single pair of probe and coupling laser pulses and by probe and coupling
laser pulse trains. We discuss the influence of the coupling pulse area, number
of pulses, and detunings on the probe laser propagation and realization of
electromagnetically induced transparency conditions, as well on the formation
of a dark state.
