Similarity is related to Like. Like is related to Board. Board is related to Desk. 
Formal is related to Father. Father is related to Relation. Foundation is a type of Relation. 
Similarity <--RelatedTo--> Like <--RelatedTo--> Board <--RelatedTo--> Desk 
Formal <--RelatedTo--> Father <--RelatedTo--> Relation <--IsA-- Foundation 