You may agree you’re thinking in Korean if you’re Korean even when you’re talking in English. It’s challenging for Koreans to convert what they’re thinking on in their mind in English while English native speakers directly say what they’re thinking in English. Surely some Korean expressions are hard to translate in English. So it’s common for Koreans to stammer when they use English. Though some Koreans think and speak in English, it’s hard to express 100% what they’re thinking in English. For example, when foreigners ask Korean people what their favorite food is, many Koreans answer they like Kimchi or Korean barbecue. Some Koreans truly love Kimchi or Korean barbecue, but many others say they like Kimchi or Korean barbecue because it’s difficult for them to describe what other foods such as Chicken soup with ginseng, rice cake and dumping soup, or seasoned skate are that they like.  I hope we do our best to practice English so that we can extend our living areas to the worldwide.