1. A legal brief or court document: The language of law requires precision, objectivity, and adherence to specific conventions. Informal language would undermine the authority and credibility of the document, potentially leading to serious consequences.
2. A scientific research paper: Scientific writing demands clarity, accuracy, and the avoidance of ambiguity. Informal language could misrepresent findings or introduce bias. The established structure and terminology of scientific papers are inherently formal.
3. A eulogy for a high-ranking government official delivered at a state funeral: The solemnity of the occasion and the importance of the deceased demand a respectful and dignified tone. Informal language would be disrespectful and detract from the gravity of the event.
While some level of formality is appropriate across many topics, these three are particularly resistant to informal approaches. Attempting an informal style would be jarring and inappropriate in these contexts.