Commitment is a synonym of Liability. Liability is related to Company. Company is related to Pet. Pet is related to Companion. 
Valuable is related to Expensive. Expensive is related to Tax. Tax is related to Share. 
Commitment <--Synonym--> Liability <--RelatedTo--> Company <--RelatedTo--> Pet <--RelatedTo--> Companion 
Valuable <--RelatedTo--> Expensive <--RelatedTo--> Tax <--RelatedTo--> Share 