In Korean the sound differences are very subtle and it is incredibly difficult to distinguish them unless your native language also includes them. For me, it is very difficult to distinguish 기, 키, and 끼, as all of them sound like "ki".
Other such differences are 벼, 뼈, and 펴 or 고, 꼬, and 코.
I read the IPA description but honestly I don't understand the difference between them even after having heard so many times. The aspirated one seems a bit different, but only a little bit different from the others and are still unbelievably difficult to distinguish, in my opinion.
So what is the difference between them in pronouncing, and how can I hear them apart better?