Hello, my teacher asked me to write a paragraph about "what's life."

Life is a characteristic that distinguishes physical entities that have biological processes, such as signaling and self-sustaining processes, from those that do not, either because such functions have ceased, or because they never had such functions and are classified as inanimate

Explanation:

Life is many things:  a game (by Hasbro), a magazine (published in 1930s - early 1970s), a personal perspective of one's years as a living being or a general reference to living.

Explanation:

I imagine your teacher wants you to write a personal perspective of your own living from earliest memory until now.  In other words, you might consider your life to be the culmination of your personal experiences and social interactions (family and friends).