（）可引起职业禁忌证：神经系统疾病
A．锰
B．三硝基甲苯
C．有机氟
D．粉尘
E．苯
参考答案：A
我们学过的长度单位有______、______、______、______、______．
Would you like your friend to Beijing with you?[ ]
A. to go
B. going
C. go
D. goes
