The students _____ at home on Sundays.[ ]
A. stay
B. stays
C. staies
D. to stay
答案:A
肱骨伸直型踝上骨折最严重的并发症是:()
A.正中神经损伤
B.畸形愈合内翻
C.前臂缺血性肌挛缩
D.骨化肌炎
E.关节僵硬
简述钾的生理功能。