Sum is a synonym of Center. Center is related to Mentor. Mentor is a type of Teach. 
Peel is related to Protection. Protection is related to Paint. Paint is related to Finger. 
Sum <--Synonym--> Center <--RelatedTo--> Mentor --IsA--> Teach 
Peel <--RelatedTo--> Protection <--RelatedTo--> Paint <--RelatedTo--> Finger 