【单选题】有关“表面结构”的基本概念,下列说法不正确的是()。
A.
为了保证零件的使用性能,在机械图样中需要对零件的表面结构给出要求
B.
轮廓算术平均偏差Ra它是在一个取样长度内,最大轮廓峰高与最大轮廓谷深之和
C.
表面结构就是由粗糙度轮廓、波纹度轮廓和原始轮廓构成的零件表面特征
【判断题】Demonstrate relationships among concepts are not belonging to the cognitive methods.()
【单选题】He attended school in England for several years, after ______ he returned home.
【单选题】A webmaster is responsible______developing and maintaining the Web site belonging to an organization or company.
【单选题】我们可以感受到,在人大和政协会议期间,国家的任何决议、法律,在表决之前都经过长时问的反复调查、研究、讨论、协商、修改,准备得比较成熟了再付诸审议和表决,给持各种意见者充分表达意愿的机会。这说明( )
【简答题】He had been an consultant for two years.
【单选题】My brother _______ the army two years ago.He has ______ for two years.
B.
joined ; been a soldier
C.
joined in ; become a soldier
【单选题】Don’t take things________ others.
【简答题】https://www.wjx.cn/m/59826066.aspx