Tex. R. Civ. P. 278
The court shall submit the questions, instructions and definitions in the form provided by Rule 277, which are raised by the written pleadings and the evidence. Except in trespass to try title, statutory partition proceedings, and other special proceedings in which the pleadings are specially defined by statutes or procedural rules, a party shall not be entitled to any submission of any question raised only by a general denial and not raised by affirmative written pleading by that party. Nothing herein shall change the burden of proof from what it would have been under a general denial. A judgment shall not be reversed because of the failure to submit other and various phases or different shades of the same question. Failure to submit a question shall not be deemed a ground for reversal of the judgment, unless its submission, in substantially correct wording, has been requested in writing and tendered by the party complaining of the judgment; provided, however, that objection to such failure shall suffice in such respect if the question is one relied upon by the opposing party. Failure to submit a definition or instruction shall not be deemed a ground for reversal of the judgment unless a substantially correct definition or instruction has been requested in writing and tendered by the party complaining of the judgment.
Tex. R. Civ. P. 278