Does a straw have one hole or two?

That's one of those questions which can be answered using the concept of limits.
If we reduce the length of the straw, the limit will be a circle of infinitesimal length, featuring exactly one hole. The shortening of the straw is a continuous process, and no hole disappears during the process.
==> a straw has one hole.
If you cut the straw in two halves, both moieties will feature one hole, so you will have two holes in this case.
The same is true for a hose. 😑