This week is the beginning of Chusok in South Korea. Often, people call it "Korean Thanksgiving," comparing it to American Thanksgiving. There are many similarities (things that are the same), but also, some differences.
Give it a try. Think about the biggest holidays in your country, and then how to describe it in English. You should talk a little about: its history, how it is celebrated (what people do), why it is important (its significance), where and when it is celebrated, and what you/your family does usually. Use a dictionary / online translator for difficult phrases and then send a description of the holiday to an English friend/friends. Ask them to correct any of the English that sounds strange or ask questions about anything they don't understand.
Here's a great video from Australia Plus about Festivals & Celebrations: