SIAMESETWINS
Siamese twins
Siamese twins in the context of the English language refers to a pair or grouping of words that is used together as an idiomatic expression or collocation, usually conjoined by the words and or or. The order of elements cannot be reversed. The expressions hammer and sickle, short and sweet, and sink or swim are various examples of Siamese twins.The above text is a snippet from Wikipedia: Siamese twins (linguistics)
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