检验机构应当在安装、大修或改造等施工单位()的基础上进行验收检验。
A.自检合格
B.通过制造单位验收
C.通过使用单位验收
D.运行无故障
参考答案:A
下列各物质中,属于金属单质的是( )
A.铁粉
B.金刚石
C.黄铜
D.不锈钢
The Browns sent lots of invitations for their party. But because of the improper time, few people _____ it.
A.attended
B.accepted
C.received
D.enjoyed