single file
noun [ S ] uk/ˌsɪŋ.ɡəl ˈfaɪl/ us/ˌsɪŋ.ɡəl ˈfaɪl/
单行，一路纵队
a way of walking with one person behind another
The schoolchildren were told to walk in single file. 小学生们被要求排成一路纵队前进。
江苏热线英汉汉英双解词典包含207361条英汉翻译词条，涵盖了常用英语单词及词组短语的翻译及用法，是英语学习的必备工具。