You'll have lots of discrepancies when you're trying to associate hangul with English letters. To be honest, English letters are your enemy... Anyway, for 연빌입니다, were you trying to say 연필? What you wrote is yeonbirimnida. 'R,' always being a rolled/hard R sound when referenced in Korean. 책들은=>chaekdeureun. Tip: You can ignore the ㅇ when it comes to ㄹ, so its essentially pronounced 책드른 Then... "I mean different collocations of words or word + qrammatical construction. Do the reading rules have affect on construction like 'noun + case'?" I'm not sure what you're trying to ask here, sorry :/