Safe is related to Home. Home is related to Shell. Shell is related to Nut. Nut is a synonym of Ball. 
Throat is a type of Passage. Throat is related to Tube. Tube is related to Rubber. Rubber is related to Balloon. 
Safe <--RelatedTo--> Home <--RelatedTo--> Shell <--RelatedTo--> Nut <--Synonym--> Ball 
Passage <--IsA-- Throat <--RelatedTo--> Tube <--RelatedTo--> Rubber <--RelatedTo--> Balloon 