Tired is a form of Tire. Tire is related to Spare. Spare is a type of Give. 
Fit is a synonym of Suitable. Suitable is a synonym of Happy. Happy is the opposite of Birthday. Birthday is related to Increasing. 
Tired --FormOf--> Tire <--RelatedTo--> Spare --IsA--> Give 
Fit <--Synonym--> Suitable <--Synonym--> Happy <--Antonym--> Birthday <--RelatedTo--> Increasing 