A: One goes choo-choo the other goes chew-chew.
And why doesn't my girlfriend share this impulse?
Once you're done enjoying the legs, thighs and breasts your left with a greasy box to stick your bone in.
A piece of gum, you pervert!
The train got windows
Because they're bad conductors.
A school teacher tells you to spit out your gum, a train says choo choo.