内侧半月板后角损伤2度:Why do we need to wash our hands freuently?

Why do we need to wash our hands freuently? Why do we need sleep We need to do my home work,____ ____? We need to do my home work,____ ____? we will need -------help to do the work (add) Why do we go to bed ?_________________?这么填写什么?? why do you need friends? why friends are important to you? why do you need sunglasses? 1.How many t___ of cinnamon do we need to make fruit salad? why do we study English ?