Understanding the nuance of the Korean expression '을 줄만 알았지'

While conducting an advanced Korean class, I came across the expression '을 줄만 알았지.' While I am familiar with the expression '을 줄 알았다,' I became curious about the nuance added by the inclusion of '만.' I want to explore how this expression is used and what meaning it conveys. The first example is '그 사람은 화를 낼 줄만 알았지 참을 줄은 몰라요.' Here, '만' emphasizes the meaning of 'I only knew that they could do that action.' In other words, it indicates that the speaker expected the other person not to perform any other actions. A similar expression is '을 줄만 알았는데,' which also emphasizes expectations about a specific action or situation. Another example is '그는 노래를 잘할 줄만 알았지 춤은 잘 못 춰요.' In this way, the use of '만' is useful for highlighting the difference between expectations and reality. These expressions help illustrate the gap between expectations and reality in Korean. If you have any questions about more examples or similar expressions, feel free to ask.