ㄴ + ㄹ
If the 받침 is a ㄴ and it is followed byㄹ or if the 받침 is a ㄹ and followed by a ㄴ, the ㄴ sound becomes a ㄹ sound. This rule also applies even if ㄹ or ㄴ appear in another word, for example "일 년"(one year) gets pronounced as "일련."
- 곤란 → "골란"
- 연락 → "열락"
The subway station "선릉역" frequently gets pronounced as "Seonleung," so the ㄴ gets pronounced as normal and the ㄹ pronounced as a /l/. Foreign names written in Hangeul also tend to ignore this rule, for example the name Henry would get transliterated as 헨리 and pronounced similarly to that of it's original English pronunciation rather than 헬리.