I am suggesting a few changes which I think will improve your essay.
*Even a machine's efficiency will decrease,and finally cease,if it is used without any break.
*It is beneficial for their health.
*and wonder why he has to study all those subjects foe which he has no aptitude/Likeness.
*Although many teachers consider it their duty to assign homework, they will gradually *realize that it is not as useful as they think it to be.
- For Teachers