【判断题】为排除缸内空气,对要求不高的液压缸,可将油管设在缸体最高处。
【单选题】It's time to say goodbye to my school. I'll always remember the people ________have
A.
49. It's time to say goodbye to my school. I'll always remember the people ________have helped me. A.who
【单选题】People everywhere celebrate the New Year. ______ is a time to say goodbye to the past and to think about new beginnings. [ ]
【简答题】如图,平行四边形ABCD中,E为AB上的一点,连接CE、BD交于F. (1)求证:△BEF ∽ △DCF; (2)若AE:EB=2:1,①求△BEF:△DCF的周长比;②若S △BEF =6cm 2 ,求S △DCF .
【单选题】_______ is time to say goodbye. [ ]
【单选题】下列说法中错误的是( )。
B.
在垂直于螺纹轴线的投影面的视图中,需要表示部分螺纹时,螺纹的牙底线也适应当地空出一段距离
C.
完整螺纹的终止界线(简称螺纹终止线)用粗实线表示
D.
当需要表示螺纹收尾时,螺纹部分的牙底用与轴线成 30 °角的细实线绘制
【单选题】It's time to say goodbye ____________ my friends. [ ]
【判断题】为排除缸内的空气,对要求不高的液压缸,可将油管设在缸体的最高处。
【单选题】在如图中,点E是直线CA上的点,∠CEG=∠BEG,∠BEF=∠AEF.则下列结论错误的是 [ ]