Ineed to write an essay about a time ive had a wrong impression about someone

I will give you an example of an essay consisting of three paragraphs below.

Explanation:

During my first day in high school, I was very hesitant to talk to my new classmates. All of them almost knew each other because they went to a similar middle school, however, I came from another country. I thought everyone was a snob until a girl suddenly approached me. She was wearing a beautiful smile, which complemented her expensive bag and accessories. I looked over my back to see whether she was calling somebody else, but she wasn't. She wanted to make friends with me.

Days passed by and we became best friends. We shared secrets together and I relied on her in many things. I thought she was the friendliest person in the world until one day. I noticed a group of people laughing at me. I was curious why. Then, one person approached me and told me that my best friend was actually telling them my secrets. Immediately, I realized that first impressions are not really true all the time. The best friend I consider was actually talking about me behind my back.

This experience made me realize that sometimes we get the wrong impression of another person. That person may seem good or bad at the start, but they turn out different in the end. It is always important to know them better before giving out your secrets.