[译] 铃响时，学生们从教室里鱼贯而出。
[误] The students came out of the classroom on file when the bell rang.

[正] The students came out of the classroom in file when the bell rang.
[注] on file 和 in file 都是惯用词组,但意思不同。on file 表示“归档,存卷”,而 in file 表示“依次,鱼贯地”。如:All those documents have been placed on file.所有那些文件都已归档。