Extend is related to Stretch. Stretch is related to Flexibility. 
Pay is related to Charge. Charge is related to Battle. Battle is a synonym of Conflict. Conflict is a synonym of Struggle. 
Extend <--RelatedTo--> Stretch <--RelatedTo--> Flexibility 
Pay <--RelatedTo--> Charge <--RelatedTo--> Battle <--Synonym--> Conflict <--Synonym--> Struggle 