防止影像变形的措施错误的是()
A.X线中心线方向和角度对变形无影响
B.被照体靠近胶片
C.中心线应垂直于胶片
D.中心线通过被检部位并垂直于胶片
E.使被照体平行于胶片
参考答案:A
根据句意及汉语提示完成下列句子
1. My mother bought me a (围巾)as a birthday present.
2. (每个人)is having a good time at the party.
3. We are very____(放松的)on the beach
4. Where are they going on (度假)?
5. In this____(热天),I only want to stay at home.
经纬仪导线的边长采用()丈量。
A、皮尺
B、钢尺
C、测绳
D、卷尺