In the acquisition of a foreign language, discerning the interplay among language skills is imperative to enhance and streamline the learning process. Our understanding of the interrelationships between language skills in the context of acquiring Turkish as a foreign language remains constrained. This study delves into the relationships among language skills in the context of foreign language acquisition by exploring the relationships between reading fluency (speed and accuracy), writing fluency (total word count, speed, and accuracy), and vocabulary (total word count, number of different words, types/token ratio) among 126 Turkish language learners. The investigation considered proficiency level (A1-C1) for comparisons, in addition to exploring the relationships between the aforementioned language skills. Reading fluency data was collected through the selection of texts from textbooks, while writing fluency data was obtained by instructing participants to engage in rapid writing for a duration of 2 minutes. Vocabulary data were derived from participants' responses in end-of-year exam papers. Data collected in 2021 across five language proficiency levels underwent statistical analyses, including one-way ANOVA and Pearson and Spearman correlations. The study found significant statistics for language proficiency levels, especially for the B2 level. Significantly, correlations emerged among reading, writing, and vocabulary. Importantly, these correlations exhibited variability with increasing language proficiency, underscoring the evolving nature of the relationship between language skills in foreign language learning.