Colonial is a synonym of Compound. Compound is a synonym of Pen. Pen is related to Poet. 
Absence is the opposite of Position. Square is a type of Position. Square is the opposite of Round. 
Colonial <--Synonym--> Compound <--Synonym--> Pen <--RelatedTo--> Poet 
Absence <--Antonym--> Position <--IsA-- Square <--Antonym--> Round 