Impose is a synonym of Enforce. Enforce is a synonym of Nerve. Nerve is a synonym of Encourage. 
you are likely to find Toilet in/at/on House. Head is a type of Toilet. Head is related to Shade. 
Impose <--Synonym--> Enforce <--Synonym--> Nerve <--Synonym--> Encourage 
House <--AtLocation-- Toilet <--IsA-- Head <--RelatedTo--> Shade 