Long is related to Monkey. Monkey is related to Tree. you are likely to find Sand in/at/on Tree. Sand is related to Dirt. 
Cluster is related to Group. Race is a type of Group. 
Long <--RelatedTo--> Monkey <--RelatedTo--> Tree <--AtLocation-- Sand <--RelatedTo--> Dirt 
Cluster <--RelatedTo--> Group <--IsA-- Race 