【简答题】[A] studying [B] studied [C] to study [D] having studied
【简答题】At the final stage of negotiation they were still reluctant to talk substance.
【多选题】在放射防护体系中和辐射实践活动中的基本原则是:
【单选题】动物口服生蛋清会引起哪一种维生素的缺乏?
【单选题】城市规划法规文件的纵向体系由所涉及的法律、法规、规章和规范性文件四个层次构成其原则是( )法律、法规。
D.
下一层次制定的法规文件要突出,较细致于上一层的