activity Web动态网站activityn.活动；活跃vt.表演adj.厉害activity of cement水泥活性activity stability活性稳定性activity on-node以结节代表作业activity investment[经] 积极投资； 投资活动activity barycentre工序重心activity motivation活动动因activity ingredient活性成分Activity Data Sheet任务资料单activity of urinary尿酶活性activity identifier活动标识符