Concentrations of troops near the border look set to invade within the next few days.

invade 是动词，意思是"入侵、侵略"，指军队进入另一个国家或地区以占领或控制它。这个词来自拉丁语 invadere，由 in-（进入）和 vadere（走）组成，字面意思是"走进去"。