Model answer
Written by 8020 teachers. Do not memorise it — take the structure and the way ideas are developed, then speak about your own life.
The person I'd talk about is a professor I had in my second year of university, Mr. Khoa, who taught a fairly unglamorous statistics module that most people in my class dreaded. I knew him only really in that academic sense — I wasn't particularly close to him personally, saw him mainly in lectures and the occasional office hour when I was stuck on an assignment. What he actually did, though, was change how I thought about a subject I'd more or less written off as something to survive rather than engage with; he had this habit of connecting every abstract concept to some genuinely interesting real-world mess — election polling gone wrong, medical trials that produced misleading results — and suddenly the material felt like it mattered rather than existing purely to be examined. He also, on one occasion when I went to his office convinced I should switch majors entirely, talked me out of it — not by flattering me, but by pointing out fairly matter-of-factly that I was better at the analytical side of my coursework than I gave myself credit for. I ended up building my entire career loosely around that side of the work, which is not something I would have predicted at eighteen. I don't think he'd remember me specifically if I ran into him now, which is a slightly strange thing to sit with, given how much that one conversation ended up shaping the career I have today.