某试验室测得几组消石灰的钙.镁含量如下,根据规范规定能用于工程的是()
A.50%
B.58%
C.60%
D.62%
参考答案:B, C, D
My brother often ____________ home at 5: 00.[ ]
A. come
B. comes
C. to come
D. comes to
两人或多人抬支架构件或物料时,要同肩、同步、口号统一、起放一致。