I would say it has been a bit beyond mastering basic dialectual nuances and more of a sociolinguistic transition, where Texan English actually exists as a sub-dialect of the
Southern American English Dialect. It is also a bit disconcerting that I still think mostly in Texan and still struggle a bit to maintain fluent English conversation, without unconsciously slipping back into my normal thick southern drawl accent.
Note the following links for reference to a few basic examples of the myriad colloquial distinctions between Texan dialogisms and that of common American English:
Texasisms: A Glossary of Texan
How to Speak Texan
Texan-English Dictionary
Also of note is that Texas English owes much of its origin to the socio-nationalistic-independent formative years during the pre-statehood Republic of Texas historical period.
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