【单选题】We have sent our union _________ to look into the case and see who is responsible.
【简答题】We have sent our union ___________________ to llok into the case and see who is responsible.
【单选题】在Windows 7的环境下,正确的是( )。
【简答题】醇按羟基所连碳原子类型不同可分为( )、( )、( )三类。
【多选题】下列是链传动的传动特点的是( )、( )、( )、( )。
B.
能在高温、油污、多尘、潮湿等恶劣的环境下工作
【单选题】As requested, we have sent you by airmail our samples. We have also (2) ________ our illustrated catalogue and pricelist with details of discount.
【单选题】下列关于链传动特点的叙述 , 不正确的是 ( )
C.
运转时 , 会产生附加动载荷 , 振动、冲击和噪声
D.
不可以用在两轴中心距较大的情况下传递运动和动力
【单选题】利用无线技术在一定局部范围内建立的网络成为( )
【单选题】We sent him our best()for his birthday.