составьте примеры к at/on/in к каждому из них по три примера срочно!

At: Meet me in the park at 7pmI want to study at the university in a couple of yearsI was at the dentist's yesterday. On: Scientists say there's water on MarsI do aerobics on a regular basis My mom always includes bread on the shopping listIn: I have been living in Russia since I was born I don't like when things are not in their places, especially when I'm looking for somethingThere are 25 (замените число на ваше) students in my class.