Great is the opposite of Terrible. Terrible is the opposite of Perfect. Perfect is a synonym of Expert. Investigator is a type of Expert. 
Talk is related to Good. Good is related to Trade. Trade is related to Stock. Stock is a synonym of Inventory. 
Great <--Antonym--> Terrible <--Antonym--> Perfect <--Synonym--> Expert <--IsA-- Investigator 
Talk <--RelatedTo--> Good <--RelatedTo--> Trade <--RelatedTo--> Stock <--Synonym--> Inventory 