Mouth is similar to Manual. Manual is the opposite of Automatic. 
Horizon is part of Perspective. Horizon is related to Distance. Leg is a type of Distance. Leg is related to Body. 
Mouth <--SimilarTo--> Manual <--Antonym--> Automatic 
Perspective <--PartOf-- Horizon <--RelatedTo--> Distance <--IsA-- Leg <--RelatedTo--> Body 