Consider these expressions:
Don't place the suitcase vertically, it will mess up all of the clothes inside. Keep it horizontally on the floor.
I keep the books vertically in my shelf unlike this arrangement.
The words horizontally and vertically sound very technical to me. I use them in physics or maths but I rarely see them in movies or books.
Is this the natural way of describing these arrangements?
Best Answer
I would perhaps say: