creeping line ahead search曲线前进式搜索
in line ahead成纵列前进
single line ahead单列前进;单纵队
Creeping Line Ahead蛇行搜索
fore spring line ahead缆
Creeping Line Ahead Search formation匍匐前行式搜索
Three years in line ahead提前三年排队
Distance to 'STOP' line ahead距停车线距离
Arrived Ahead Line到前方一条线