维生素不能起到的作用是[ ]
A.调节新陈代谢
B.预防疾病
C.供给能量
D.维持身体健康
答案:C
Thanks _____ the photo ____ your family. [ ]
A. of; for
B. of; in
C. for; of
D. for; in
怎样下设孔口管?