Beat is related to Heat. Heat is related to Purpose. 
Worker is related to Guard. Guard is the opposite of Inmate. Inmate is a type of Resident. Metropolitan is a type of Resident. 
Beat <--RelatedTo--> Heat <--RelatedTo--> Purpose 
Worker <--RelatedTo--> Guard <--Antonym--> Inmate --IsA--> Resident <--IsA-- Metropolitan 