隐蔽conceal;take cover
活动手段多样、～，很有迷惑性carry out deceptive activities by resorting to different tactics and in disguised forms/公开的和～的活动over and covert activities/～发射阵地concealed firing position/～工作work under cover/～运动concealed movement（军）/～真实身份conceal one’s true identity/～阵地covered position /～得十分巧妙well-concealed;under ingenious concealment |