确诊椎动脉型颈椎病的首要检查是
A.X线平片检查
B.MRI检查
C.椎动脉造影检查
D.CT检查
E.椎动脉血流图
参考答案:C
验算建筑物沉降是否在容许范围内,为什么首先要区分变形特征?
She doesn't send emails _____ watch movies on computer. [ ]
A. and
B. or
C. so
D. but