It depends on which consonant it is. In this case because of the nasalization rule, consonants that make a 't' sound when they are the final consonant (ㅅ,ㅆ,ㅈ,ㄷ, ㅌ,ㅊ) will change to an 'n' sound (ㄴ) when the first consonant in the next sllyable is ㅁ or ㄴ. So 존댓말 would actually be pronouced as 존댄말.

예뻐진 여자 is actually past tense because adding 지다 turns it into a action verb . If you use 은/ ㄴ instead of 는(present tense) it will indicate a past state. So 예뻐진 여자 is a girl who has already become pretty. 예뻐지는 여자 is a girl that is becoming prettier and 예뻐질 여자 is a girl that will become pretty. So use the verb+ ㄹ/을 +noun form to show future tense noun modification.

쌍둥이

촬영이 재미있으면서도 힘들었어요 촬영-photoshoot, filming, 재미있다-fun, interesting 힘들다-difficult, arduous, exhausting 으면서도- used when aspects of a situation conflict with each other

1. What's your favorite animal? (제일/ 가장) 좋아하는 동물이 뭐예요? Only use 을/를 when a noun is receiving an action. 2. What's your favorite color? (제일 or 가장) 좋아하는 색깔이 뭐예요? 은 might imply that the topic of colors has been introduced already. 3. Do you think that ghosts are real 귀신/ 유령이 진짜인 것 같아요? Do you think ghosts exist? 귀신/유령이 존재하는 것 같아요? Never use 당신 unless you are trying to make someone angry. Sometimes it's used between married couples but I hear it's still not all that common. If you want to address someone use their name or title or 너 if you are really close or if it is obvious who the subject is just leave it out entirely. 4. Do you know Spanish? 스페인어를 할 줄 알아요? 5. Do you like chocolate chip cookies? 초콜릿 칩 쿠키를 좋아해요?

I think it's short for 야 이놈아 or 야 임마. 놈 means something like "guy, dude, jerk, bloke". Guys use it to address their guy friends. In this case it could be translated as "hey you!".