Syntax was a composition of rules for sentences in a language.
By 2151, Klingonese had eighty polyguttural dialects constructed on an adaptive syntax. Upon encountering Klaang that year, the universal translator of Hoshi Sato wouldn't lock on to his dialect, so the syntax didn't align. (ENT: "Broken Bow")
Later that year, when Sato was learning Denobulan, Phlox commented on her improving syntax. (ENT: "Dear Doctor")
Data suggested in 2364 that Lore's abilities, his use of syntax and grammar, were due to him being given Human memories similar to Data's own. (TNG: "Datalore")
In 2370, the Skrreean language had such a different syntax and grammar compared to languages in the Federation database, that it took the universal translators aboard Deep Space 9 longer than usual to translate their language. (DS9: "Sanctuary")
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