骨折愈合的最终阶段应是()
A.骨性骨痂形成
B.骨改建
C.纤维性骨痂连接
D.骨样组织中有钙盐沉着
E.完成了软骨化骨过程
参考答案:B
Great changes have taken place in that school. It is no longer _______ it was 20 years ago, _______ it was so poorly equipped.
A.that; which
B.what; when
C.what; which
D.which; that
简述公路水运安全技术管理的主要措施。