Trailer is related to Cheap. Cheap is related to Talk. People can be used for Talk. People is related to Department. 
Surface is related to Top. Top is a type of Hit. Seat can be used for Hit. 
Trailer <--RelatedTo--> Cheap <--RelatedTo--> Talk <--UsedFor-- People <--RelatedTo--> Department 
Surface <--RelatedTo--> Top --IsA--> Hit <--UsedFor-- Seat 