【单选题】下列化合物中最不容易发生傅克反应( Friedel-Crafts )的是
【单选题】(P139)除了生产力与生产关系的矛盾,另一对社会基本矛盾是
【单选题】As a master's candidate, he was always diligent in his study and research.
【单选题】As a result of sophisticated technologies, this device has several advantages over like products.
【单选题】盆式橡胶支座在竖向设计荷载作用下,荷载试验的检验荷载取支座设计承载力的( )倍。