Nobita and Doraemon use a digging machine to build their own subway as a birthday present for Nobita's father so he doesn't have to take the very crowded public subway to work.
Nobita y Doraemon usan una máquina de excavación para construir su propio metro como regalo de cumpleaños para el padre de Nobita para que no tenga que tomar el muy concurrido metro público para ir a trabajar.
