Get is related to Have. Sustain is a type of Have. Carry is a type of Sustain. Carry is a synonym of Maintain. 
Gentle is the opposite of Tough. Tough is related to Experienced. 
Get <--RelatedTo--> Have <--IsA-- Sustain <--IsA-- Carry <--Synonym--> Maintain 
Gentle <--Antonym--> Tough <--RelatedTo--> Experienced 