✔ 最佳答案
You have to watch more English News on TV and practise your oral by reading some English newspaper every day. You may spend half an hour to one hour to practise. Maybe, the English of your Korean colleagues may not be as good as you expected. You can ask them what they mean when you don't understand. Don't be shy to ask. The more you ask, the more you understand their accent. Sometimes, we don't even understand our own language when we use it for communication. This is usual.
Practice makes perfect.