Wheat is related to Flour. Flour is related to Bread. Bread is related to Wonder. Wonder is a type of Question. 
Clean is similar to Perfect. Perfect is related to Song. Song is a synonym of Strain. 
Wheat <--RelatedTo--> Flour <--RelatedTo--> Bread <--RelatedTo--> Wonder --IsA--> Question 
Clean <--SimilarTo--> Perfect <--RelatedTo--> Song <--Synonym--> Strain 