Foreigner is related to Illegal. Illegal is related to Crime. Pollution is a type of Crime. 
Chronic is related to Fatigue. Fatigue is similar to Duty. Duty is related to Policeman. 
Foreigner <--RelatedTo--> Illegal <--RelatedTo--> Crime <--IsA-- Pollution 
Chronic <--RelatedTo--> Fatigue <--SimilarTo--> Duty <--RelatedTo--> Policeman 