Improvement is related to Home. Home is the opposite of Travel. Pan is a type of Travel. Pan is related to Vessel. 
Duty is related to Responsible. Responsible is a synonym of Own. Own is a synonym of Possess. Possess is related to Take. 
Improvement <--RelatedTo--> Home <--Antonym--> Travel <--IsA-- Pan <--RelatedTo--> Vessel 
Duty <--RelatedTo--> Responsible <--Synonym--> Own <--Synonym--> Possess <--RelatedTo--> Take 