What is an example of metaphor in the novel, Iza’s Ballad?

The tram acts as a metaphor for Ettie's life in Budapest. As she rides the trams from one end of the track to the other, day in and day out, she is not making any progress, just going through the motions. Similarly, the trams do not really go anywhere, just from one point to the next and back again. In changing lines, Ettie breaks up the mind-numbing tedium of the routine, but again, she is not making progress as it is the same process in a different direction. At the end of each day she ends up back where she started, but another day has passed, bringing her closer to death.