中国药典中，用原子吸收分光光度法检查维生素C中
A．铁盐
B．汞盐
C．铜盐
D．砷盐
E．锌盐
参考答案：A,C
先天性髋关节脱位1岁以内可使用带蹬吊带法。()
Now Tom with his classmates ________ football on the playground.
A．play
B．are playing
C．plays
D．is playing
