Lamp is related to Electric. Electric is a type of Car. Car is related to Mechanic. 
Unique is similar to Unusual. Unusual is similar to Extraordinary. Extraordinary is related to Superior. 
Lamp <--RelatedTo--> Electric --IsA--> Car <--RelatedTo--> Mechanic 
Unique <--SimilarTo--> Unusual <--SimilarTo--> Extraordinary <--RelatedTo--> Superior 