The category "<formation-subformation>" can be expressed as follows:

<formation-subformation>

<det-not_other-indef-sing> <formation_setting>

<det-not_other-indef-sing> <formation_setting-formation> <formation_level-formation>

<det-not_other-indef-sing> <formation_setting-subformation> <formation_level-subformation>

<formation_setting> <formation_level>