Boss is related to Teacher. Teacher is related to Instructor. Instructor is related to Thing. Thing is a synonym of Concern. 
Observer is a type of Expert. Expert is a synonym of Perfect. Perfect is related to Complete. Complete is similar to Blank. 
Boss <--RelatedTo--> Teacher <--RelatedTo--> Instructor <--RelatedTo--> Thing <--Synonym--> Concern 
Observer --IsA--> Expert <--Synonym--> Perfect <--RelatedTo--> Complete <--SimilarTo--> Blank 