海伦1211的灭火作用主要是阻碍燃烧的链锁反应。
参考答案:错
The government had hoped to draw as much attention as possible to this problem but it didn’t ______that way.
A.work out
B.give out
C.go out
D.pick out
监理单位与建设单位、承建单位的关系都是( )关系。
A.建筑市场平等主体
B.合同
C.监理与被监理
D.委托服务