The category "<enemy_loc-gapsout_null-gapsin_null>" can be expressed as follows:

<enemy_loc-gapsout_null-gapsin_null>

<enemy_phrase>

<enemy_phrase> <direction>

<enemy_phrase> <engagement_loc_mod-gapsout_null-gapsin_null>

<engagement_loc-gapsout_null-gapsin_null>