Stranger is a synonym of Alien. Alien is a type of Software. Exist is a type of Software. Exist is related to God. 
Sweet is the opposite of Dry. Dry is related to Dirt. Dirt is a type of Material. Material is similar to Crucial. 
Stranger <--Synonym--> Alien --IsA--> Software <--IsA-- Exist <--RelatedTo--> God 
Sweet <--Antonym--> Dry <--RelatedTo--> Dirt --IsA--> Material <--SimilarTo--> Crucial 