In China "subway" doesn't mean train, tramps, or even a sandwitch. It just means an underground pathway to cross the street for pedestrians.

You can't imagine how painful it is in the middle of summer, when you're a fat ass foreigner clinching to the one phrase you understand in all the billboards and street signs. In one night, I must have spent 45 minutes running in underground tunnels, exploring pathways in 100 degree heat and poping up on opposite sites of the same damn intersection without finding a single train :-(

Very expensive lesson.