It’s funny because I think learning Korean has somewhat ruined my perception of the sounds in other languages — I now sometimes have a hard time distinguishing ‘r’ and ‘l’ or ‘t’, ‘d’, and ‘n’ in other (phonetically easier) languages. I never had a hard time distinguishing between ‘r’ and ‘l’ before.

Similarly, if I’m reading or thinking in Korean I sometimes make ‘he’/’she’ mistakes if I try suddenly to speak in English.