Class is related to Chemistry. Chemistry is related to Subject. 
Snap is a synonym of Crack. Crack is a synonym of Check. Check is a type of Attack. Attack is a synonym of Attempt. 
Class <--RelatedTo--> Chemistry <--RelatedTo--> Subject 
Snap <--Synonym--> Crack <--Synonym--> Check --IsA--> Attack <--Synonym--> Attempt 