井筒解堵时，可以采用（）方法解堵和锅炉车热力解堵。
A、捞矛
B、刮削器
C、机械
D、钢丝绳
参考答案：C
大机盘车启动条件？
At the conference, political leaders from many countries promised to work together to defend the world
_____ terrorism and other threats. [ ]
A. for
B. without
C. beyond
D. against
