What did you learn from these experiences and what do they reveal about you? It could instead be a way to show that you believe Harvard is just one piece of your aspirations for your education and growth. The most important thing is to convey how you might contribute in a meaningful way.
These can be as formal as extracurricular pursuits that have led to CV-worthy accomplishments or awards, or as informal as particularly well-expressed pieces of emotional growth or maturation as a result of circumstance. Furthermore, Harvard also values unique and interesting academic interests, such as partaking in anthropology research, as this demonstrates going beyond your academic requirements.
Each title is a means of interacting with the world of ideas and communicates something significant about you.
One way to successfully execute this essay is to order the titles in such a way that shows your progression through a topic.
Consider what drew you to your extracurricular activity of choice in the first place. How might your background make Harvard a particularly good fit for you? What would you do to contribute to the lives of your classmates in advancing this mission?
Perhaps it has connected you with a small, but like minded group of individuals and has allowed you to find your inner circle. Similar to the previous example, perhaps this experience heightened your passion for history and created a newfound love for linguistics, as you began to notice both the subtle and drastic differences between languages.
The more information you can provide to make you sound like a well-rounded, complete applicant, the better.