Condition is a type of Teach. Teach is a type of Inform. Prompt is a type of Inform. Prompt is a synonym of Remind. 
Buy is related to Cash. Cash is related to Bank. Bank is related to Finance. Back is a type of Finance. 
Condition --IsA--> Teach --IsA--> Inform <--IsA-- Prompt <--Synonym--> Remind 
Buy <--RelatedTo--> Cash <--RelatedTo--> Bank <--RelatedTo--> Finance <--IsA-- Back 