“三人一组”常见的英文表达有：
in groups of three
例如：The students were asked to work in groups of three for the project.（学生们被要求以三人一组的形式完成这个项目。 ）
three to a group
例如：We'll divide ourselves into teams, three to a group.（我们将把自己分成小组，三人一组。 ）