Ядро и периферия в частите на речта
Parts of speech – each one and all of them together – do not constitute closed systems. Core and periphery can be distinguished within each word class. The core is defined with reference to both the prototypical semantics and function and the prototypical grammatical category characteristic of the relevant part of speech. The periphery includes borderline words, which due to their non-core semantics exhibit grammatical properties typical both for the word class they belong to and for other classes. Different degrees of remoteness between the core and the periphery can also be observed.
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