you are likely to find Clerk in/at/on Shop. Shop is related to Mechanic. Mechanic is etymologically related to Machine. 
Recognize entails/necessarily involves Perceive. Recognize is related to Understand. 
Clerk --AtLocation--> Shop <--RelatedTo--> Mechanic --EtymologicallyRelatedTo--> Machine 
Perceive <--Entails-- Recognize <--RelatedTo--> Understand 