Hello Jake! Thank you for sharing your story. Have a great evening! Here are your corrections. ^_^

I work at the largest company in Korea. Because our company is a large company with many components, we all had to go through a business training period. Our company always emphasize education. So the training period is longer than other companies training period. The first training was from January to February. The training was about computer programming and database. Although, my job is about sales, not computer programming and database, our company gave me lectures about them as a basic training. It was so difficult for me to understand them. The second training was last March. Its period was intensive and it lasted for 3 weeks. I entered the training center. I wasn't able to sleep well because of the hectic schedules. I had to learn the history of the company, the company’s affiliations, the company’s inner workings and business etiquette. Although, the experience was very tough, I learned a lot. I got closer to all of my teammates. I think I had a good start to my new working life.