Conclusion is the opposite of Introduction. Introduction is related to Book. Book is related to Weird. Weird is similar to Strange. 
Everyday is a synonym of Casual. Casual is the opposite of Necessary. Necessary is related to Have. 
Conclusion <--Antonym--> Introduction <--RelatedTo--> Book <--RelatedTo--> Weird <--SimilarTo--> Strange 
Everyday <--Synonym--> Casual <--Antonym--> Necessary <--RelatedTo--> Have 