佝偻病激期的骨X线表现
A.此期常无骨骼改变
B.残留不同程度的骨骼畸形
C.出现不规则的钙化线
D.骨骺端钙化带消失,成杯口样改变
E.骨骺端钙化带致密
参考答案:D
He ______ be a history teacher.
A.used to
B.be used to
C.use to be
D.be use to
氧气站的危险点是()
A.易燃、易爆炸
B.破裂
C.失效
D.漏氧气