Given a pair of words, deduce the type of relationship between them. The various types of relations are: 'Entails, HasProperty, Synonym, Antonym, HasA, MemberOf, PartOf, MadeOf, IsA'. Let's denote the first word by X and the second word by Y. An 'IsA' relation holds when 'X is a kind of Y'. An 'Antonym' relation holds when 'X can be used as the opposite of Y'. A 'Synonym' relation applies when 'X can be used in place of Y, without changing the meaning'. A 'PartOf' relation holds when 'X is a part of Y'. A 'MemberOf' relation holds when 'X is a member of Y'. A 'MadeOf' relation holds when 'X is made of Y'. An 'Entailment' relation holds when 'If X is true, then Y is true as well'. A 'HasA' relation holds when 'X can have or contain Y'. A 'HasProperty' relation holds when 'Y is to specify X'.
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Question: X: bend, Y: bow

Answer: Synonym


Question: X: automobile, Y: car

Answer: Synonym


Question: X: back, Y: main

Answer:
Antonym