接触氧化法所用的填补按安装方式分为（）。
A.固定式、悬浮式
B.固定式、悬浮自由式
C.固定式、自由式
D.悬浮式、自由式
参考答案：B
He is no longer in good condition, and his ability to work is limited. I _______ him to give up the job but failed.
A．suggested
B．persuaded
C．tried to persuade
D．managed
依据《中国南方电网有限责任公司电力安全工作规程》切割作业的规定，氧气瓶软管连接处应用专用卡子卡紧或用（）扎紧。
A.软金属丝
B.塑料扎带
C.细绳
D.硬金属丝
