I thought of a question, what should Mulan do when she goes to the toilet when she joins the army

This starts with Mulan's position.

In fact, when Mulan joined the army, she was not a soldier in the war, she was a communication soldier, so most of the time she rode around alone.

And because this kind of communication soldier has important documents on him, he stays alone at each post station, which solves the problem of her being a daughter.

Literary works are originally allowed to be fictional, and the focus of this poem is to illustrate Mulan's bravery, being able to lead troops to kill the enemy and fight like men, as for going to the toilet and bathing and the like, if you insist on pursuing it, it can't stand scrutiny, and being together for so long is enough to leak a bunch of flaws, so the focus should be on Mulan's bravery, not whether she was found out about her daughter, which is really a secondary matter.