请教一下，C# link如何实现转折查询

请教一下，C# link如何实现转折查询？比如每3个结果换行？

query = query.Select((x, i) => new { x, i })
.GroupBy(x => x.i / 3).Select(x => x.Select(y => y.x))

query = query.Select((x, i) => new { x, i })
.GroupBy(x => x.i / 3)