A corpus-based evaluation of lexical authenticity in Turkish as a foreign language (TFL) textbooks

Textbook authors frequently assert that their materials offer a comprehensive and authentic representation of language, mirroring real-life communication. This study critically examines these assertions by conducting a large-scale comparative analysis of Turkish as a Foreign Language (TFL) materials, specifically the Yeni İstanbul series, against a 5-billion-word reference corpus (trTenTen20), the Turkish National Corpus (TNC). The findings reveal substantial discrepancies in word frequency and a lack of natural-sounding collocations within textbooks, suggesting that reliance on author intuition alone may limit a learner’s exposure to the richness and diversity of authentic Turkish.