Habitat is related to City. City is related to Sex. Sex is related to Aggression. 
Send is a synonym of Pass. Pass is a synonym of Suffer. Suffer is related to Anxiety. Anxiety is a synonym of Trouble. 
Habitat <--RelatedTo--> City <--RelatedTo--> Sex <--RelatedTo--> Aggression 
Send <--Synonym--> Pass <--Synonym--> Suffer <--RelatedTo--> Anxiety <--Synonym--> Trouble 