The rules that use the vocabulary item "units" are:

<enemy_noun>

enemy units

<unit_n>

units

<unit_n-not_det-pl>

units

<unit-not_except>

<det-not_other-not_indef-pl> <call_sign_prefix> units

<unit>

<det-not_other-not_indef-pl> <call_sign_prefix> units

<det-not_other-not_indef-pl> <call_sign_prefix> units <except> <unit-not_except>

<unit_n-pl>

units

<unit-pl>

<det-not_other-not_indef-pl> <call_sign_prefix> units

<det-not_other-not_indef-pl> <call_sign_prefix> units <except> <unit-not_except>

<enemy_noun-mobile>

enemy units