In this article, we study the effects of the atomic motion and the field-mode structure on the entropies and entanglement of a generalized JC model. We have investigated different forms of the intensity dependent function on the evolution of the entropies and entanglement in the case of a coherent superposition state and a statistical mixture of coherent states as the initial field states. We investigate the partial entropies of the atom and field subsystems numerically. The setting of the initial state of the field-mode and the atomic motion plays an important role in the evolution of the sub-entropies and entanglement.