demanding

Being a professional athlete is a very demanding career that leaves little free time.

(Chinese) 成为一名职业运动员是一项非常辛苦的职业，几乎没有空闲时间。

The music teacher was very demanding, insisting that her students practice for four hours daily.

(Chinese) 这位音乐老师非常严苛，坚持要求她的学生每天练习四个小时。