（）是保障工程安全和人身健康的重要手段。
A.国家标准
B.地方标准
C.企业标准
D.工程建设标准
参考答案：D
如何进行业务咨询？
—Look at the noisy kids.
—Haven't you heard the saying "When the cat is away, the mice ______."[ ]
A. will play
B. played
C. are playing
D. plays
