tail back
phrasal verb with tail verb [ T ] uk/teɪl/ us/teɪl/
UK
（车辆）排起长龙
If traffic tails back, it forms a long line and moves very slowly or stops.
There is traffic tailing back along the motorway for ten miles because of road repairs. 由于道路维修，车辆在高速公路上排起了10英里的长龙。