Hang is related to Arm. Arm is related to Elbow. Elbow is related to Bone. 
Cell is related to Bacteria. Bacteria is related to Disease. Disease is related to Epidemic. 
Hang <--RelatedTo--> Arm <--RelatedTo--> Elbow <--RelatedTo--> Bone 
Cell <--RelatedTo--> Bacteria <--RelatedTo--> Disease <--RelatedTo--> Epidemic 