Snow is the opposite of Summer. Summer is related to Warmth. you are likely to find Warmth in/at/on Oven. 
Examination is related to Observation. Observer is part of Observation. Observer is part of Experiment. Experiment is a type of Venture. 
Snow <--Antonym--> Summer <--RelatedTo--> Warmth --AtLocation--> Oven 
Examination <--RelatedTo--> Observation <--PartOf-- Observer --PartOf--> Experiment --IsA--> Venture 