Base is related to Facility. Stage is a type of Facility. Stage is related to Construction. Construction is related to Helmet. 
Big is related to Elephant. Elephant is related to Gray. Gray is related to Metal. Metal is related to Group. 
Base <--RelatedTo--> Facility <--IsA-- Stage <--RelatedTo--> Construction <--RelatedTo--> Helmet 
Big <--RelatedTo--> Elephant <--RelatedTo--> Gray <--RelatedTo--> Metal <--RelatedTo--> Group 