Bathrooms are laid out with toilets against a wall. Always. Unless you are a king and have a toilet in the middle of the room. Very unusual, to say the least.

Therefore, nothing can ever be "behind" a toilet. The front and the back of a toilet are "set things". They don't change depending on your point of view.

When any built structure has items up against a wall like a toilet, there is a front (where you feet go) and a back to the toilet that is up against the wall. The back of the element is against a wall (sink and toilet) and the front sides face outwards. This is pretty much standard in the Western world.

Even if there is a partially obstructed view, one would not say the toilet is behind the sink. The toilet and sink in the picture are next to each other.

So, teacher, you were right and your student was mistaken. And I believe this is probably the same thing in most languages.

Bathrooms are laid out with toilets against a wall. Always. Unless you are a king and have a toilet in the middle of the room. Very unusual, to say the least.

Therefore, nothing can ever be "behind" a toilet. The front and the back of a toilet are "set things". They don't change depending on your point of view.

When any built structure has items up against a wall like a toilet, there is a front (where your feet go) and a back to the toilet that is up against the wall. The back of the element is against a wall (sink and toilet) and the front sides face outwards. This is pretty much standard in the Western world.

Even if there is a partially obstructed view, one would not say the toilet is behind the sink. The toilet and sink in the picture are next to each other.

So, teacher, you were right and your student was mistaken. And I believe this is probably the same thing in most languages.