Sole is etymologically related to Soil. Sole is the opposite of Corporation. Corporation is related to Rock. 
Breathing is a form of Breathe. Sigh is a type of Breathe. Sigh is related to Deep. Deep is similar to Profound. 
Soil <--EtymologicallyRelatedTo-- Sole <--Antonym--> Corporation <--RelatedTo--> Rock 
Breathing --FormOf--> Breathe <--IsA-- Sigh <--RelatedTo--> Deep <--SimilarTo--> Profound 