lets say you grabbed a shovel, went into the garden and dug a small hole. it is one hole. there can be various sizes and labels, such as gully, ditch, crater, chasm, etc. now imagine that hole went all the way through the earch to the other side of the world. still only one hole isnt it? it's just one hole with multiple entrances. When you go caving, you may find that one cave has multiple entrances and exits out of the mountainside, but its still the same cave. You can apply the same thing to straws. Still only one hole, but with 2 entrances/exits.