English translation for "第二级活动"

secondary activity
secondaryactivity

Similar Words：

"第二级工作高度" English translation, "第二级光谱" English translation, "第二级光谱（色像差）" English translation, "第二级光谱，第二级谱" English translation, "第二级光谱双线" English translation, "第二级火箭" English translation, "第二级火箭发动机" English translation, "第二级记忆" English translation, "第二级减速小齿轮" English translation, "第二级酒" English translation