不属于产后早期活动的好处是
A.有利子宫复旧
B.有利于大小便通畅
C.有利于盆底肌张力恢复
D.有利于泌乳
E.防止下肢静脉血栓形成
参考答案:D
I want _____ the classroom. Could you _____ me, please? [ ]
A. clean, help
B. to clean, help
C. clean, to help
D. to clean, to help
氮素有哪些营养功能?