what is the military unit whose command structures are 2nd marine expeditionary brigade and 2nd marine expeditionary brigade ?
SELECT DISTINCT var_uri where brack_open var_uri dbo_commandStructure dbr_2nd_Marine_Expeditionary_Brigade sep_dot var_uri dbo_commandStructure dbr_2nd_Marine_Expeditionary_Brigade sep_dot var_uri a dbo_MilitaryUnit brack_close