single file

Before the men were taken to the various places of labor, they were ranged in single file, and their numbers called out.

They took one more sharp look around, then walked, single file, up the narrow passage to the control room.

Twelve women in single file were picking their way across the mushy street piled with soft March snow.

A moment later three men walked, single file, into the room.

Po Lun leading, they went, single file through utter blackness.

The nine girls started through the hall and down the broad stairway in single file.

All being ready, in single file they entered the mouth of the cavern, carefully groping their way, not without difficulty.

The sides of the notch were steep, and the boys rode through it in single file, Matt taking the lead.

The seven military judges of the Council of War advanced solemnly, in single file.

The path sank into a choking vegetation that stood on either side and brushed their faces as they followed in single file.