Express is related to Speed. Speed is related to Limit. 
Unit is related to Colony. Bee is part of Colony. you are likely to find Bee in/at/on House. House is related to Lawn. 
Express <--RelatedTo--> Speed <--RelatedTo--> Limit 
Unit <--RelatedTo--> Colony <--PartOf-- Bee --AtLocation--> House <--RelatedTo--> Lawn 