a fifth column
organized group of people working for the enemy within a country at war 第五纵队（战时在国内为敌人工作的组织）.
1. Who has not stood in awe at the sight of a spider pouncing on a fly, or a column of ants triumphantly bearing home an enormous dead beetle?
2. He was hurt in the spinal column.
3. One column of smoke with one gunshot meant an enemy troop of about 100, two columns with two shots meant 500.
4. For three minutes I flapped on the whistling, pounding, deafening column of wind.