题型:选择题 Bob bought his phone several years ago and it is _____ now. He is going to buy a new one. [ ]A. out of style B. in style C. on board D. at least 查看答案
题型:选择题 下列叙述中正确的是A.除零族元素外,所有短周期元素的最高化合价在数值上都等于该元素所属的族序数B.除短周期外,其他周期均有18种元素C.副族元素中没有非金属元素D.碱金属元素是指ⅠA族的所有元素 查看答案