事故发生后，事故现场有关人员应当立即向本单位负责人报告；单位负责人接到报告后，应当在

数据的基本单位是　【5】　。

木棍在水面振动会产生______；说话时声带的振动在空气中形成______．导线中电流的迅速变化会在空间激起______，它虽然看不见、摸不到，但是我们可以用实验的方法探测到它，所以它是______．

It’s very_______ to talk_______ him.

A．pleasure, to

B．pleased, with

C．pleasant, with

D．pleased, to

用所给单词的适当形填空。

 l. We know many ________ ( hero) in the movie.

2. I was _________ at the ________ news very much ( surprise).

3. I happened___________(see) my teacher on the way to school.

4. After two hours' discussion, they made a hard__________(decide).

5. Tom is so___________ (luck) that he wins the contest again.

违反《建设工程安全生产管理条例》规定，施工单位使用未经验收或者验收不合格的（）的责令限期改正。

A.施工起重机械

B.整体提升脚手架

C.焊接设备

D.钢筋混凝土机械

E.自升式模板