Hand is part of Arm. Hand is related to Related. Related is related to Employ. Employ is related to Hire. 
Pc is a type of Computer. Computer is related to Energy. Energy is related to Electricity. 
Arm <--PartOf-- Hand <--RelatedTo--> Related <--RelatedTo--> Employ <--RelatedTo--> Hire 
Pc --IsA--> Computer <--RelatedTo--> Energy <--RelatedTo--> Electricity 