Our Master Is a Sword

Su Yan traveled through time and became a sword, and the system must be charged to 100% by recruiting disciples before he can return to the original world. I thought it would be an easy job, but the apprentices he accepted were more and more weird than the last. The eldest brother has no brains, the second child is unhappy, the third child is short-sighted, and the fourth child is stubborn. Master says but doesn't listen, listens but doesn't understand, understands but doesn't do it, does it but does it wrong, does it but doesn't admit it, admits it but doesn't change it, changes it but doesn't accept it, and doesn't say anything if he doesn't accept it. However, it was not until later that Su Yan understood that while teaching his disciples, he was also being subtly changed. Time flies like lightning, and when the trees are about to become quiet, the wind doesn't stop... (There is no heroine in Changsheng's apprenticeship, and daily relaxation is very healing~)