I agree with SeanEJ. The thing that you have to do firstly is to learn the Korean alphabet and basic words. Because without this, it's hard to communicate with Korean in Korean. Also, Korean grammar is very different to English grammar. So It's better to know even few of them. But after you master the Korean alphabet, you can make any sound with Hangul by mixing them. Is there any Korean around you?

Why are you looking at me? 왜 쳐다봐? -You can say that when anybody look you Why are you looking at me like that? 왜 그렇게 쳐다봐? -You can use this sentense when someone stare you little bit long time or strangely or non-generally or etc. When you think there are some reason that someone look at you. Is something on my face? 내 얼굴에 뭐 묻었어? It has a same mean - "why are you looking at me like that?" What's wrong? 무슨일이야 There's nothing wrong. Everything is fine. 별 일 없어. 다 좋아. What's wrong with me? 나에게 무슨일이 생긴거지? What's wrong with you? 무슨일이야? Why are you like that? 너 왜 그래?

Oh ㄹ is similar with 'R' or 'L' in English~