you are likely to find Leg in/at/on Pair. Pair is a type of Arrange. Organize is a type of Arrange. 
Person wants (to) Support. Maintenance is a type of Support. Maintenance is derived from Maintain. Maintain is a synonym of Assert. 
Leg --AtLocation--> Pair --IsA--> Arrange <--IsA-- Organize 
Person --Desires--> Support <--IsA-- Maintenance --DerivedFrom--> Maintain <--Synonym--> Assert 