Inevitable is related to Fate. Fate is the opposite of Chance. Chance is the opposite of Chest. Chest is related to Toy. 
Combined is a synonym of Joint. Joint is related to Bar. Bar is a synonym of Pipe. Pipe is related to Stem. 
Inevitable <--RelatedTo--> Fate <--Antonym--> Chance <--Antonym--> Chest <--RelatedTo--> Toy 
Combined <--Synonym--> Joint <--RelatedTo--> Bar <--Synonym--> Pipe <--RelatedTo--> Stem 