The hierarchy of menus has been flattened down until it is only one level deep .

这里菜单只有一级，层次关系扁平化了。

youdao

With ActiveRecord, you can also nest the: include option, but only one level deep.

通过ActiveRecord，还可以嵌套：include选项，但嵌套深度只有一级。

youdao

With ActiveRecord, you can also nest the: include option, but only one level deep.

通过ActiveRecord，还可以嵌套：include选项，但嵌套深度只有一级。

youdao