阳性对比剂的特点,错误的是()
A.比重大
B.原子量低
C.X线不易透过
D.X线衰减系数大
E.碘制剂都是阳性对比剂
参考答案:B
解析:阳性对比剂原子序数高。
Mr. Green taught _____ English in our school and taught _____ French at home.[ ]
A. us, his
B. him, us
C. our, himself
D. us, himself
什么是培训方案?