【判断题】解放前,我国大约有60多万民族人口保持着完整的奴隶制度。( )
【单选题】在小组开启阶段表现出来的小组动力特征包括( )
【单选题】为了提高齿轮传动的接触强度,可采取 的方法。
【判断题】为了提高齿轮传动的接触强度,可采取采用闭式传动的方法。()
【简答题】He made a ______ decision when he went into advertising. (fortunately)
【单选题】Mr. Wang made up his mind to devote all he could _____ his oral English before going abroad. [ ]