The student was considered infirm of purpose due to his lack of motivation to complete assignments.
由于缺乏完成作业的动力，这个学生被认为意志薄弱。
Educators often work with students who are infirm of purpose to help them develop stronger willpower.
教育工作者经常与意志薄弱的学生合作，帮助他们培养更强的意志力。