Related is related to Cross. Cross is related to Mark. Mark is related to Scratch. Scratch is a synonym of Strike. 
Balloon is related to Toy. Toy is related to Tree. Tree is related to Pole. 
Related <--RelatedTo--> Cross <--RelatedTo--> Mark <--RelatedTo--> Scratch <--Synonym--> Strike 
Balloon <--RelatedTo--> Toy <--RelatedTo--> Tree <--RelatedTo--> Pole 