We were walking in single file to the lake.

我们排成单行走向湖边。

《柯林斯英汉双解大词典》

They made their way in single file along the cliff path.

他们一个接着一个沿悬崖小径前进。

《牛津词典》

However, a portlet can only be developed as a WAR file; you cannot deploy a portlet and an EJB in single file.

然而，portlet只能作为WAR文件来开发，您不能在单个文件中部署portlet和EJB。

youdao

The picture shows the band members walking in single file on a zebra crossing in north London's Abbey Road.

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They stood stiffly, took no questions and walked out in single file.

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Hours later, with the night sky dark, protesters re-entered the park in single file, after they were allowed back in, as long as they didn't bring camping equipment.

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