生物陶瓷具有以下哪些特点()
A.生物相容性差
B.有骨引导作用
C.机械强度好
D.脆性大
E.加工性能好
参考答案:B, D
I go to school by _______, but my best friend goes there ______foot.
A.a bike; by
B.bikes; on
C.bike; on
D.bike; by
家畜喉软骨中,成对存在的软骨是()
A.甲状软骨
B.会厌软骨
C.杓状软骨
D.环状软骨
E.气管软骨