What is the function of 나 & 이 in this phrase. 요즘 나무집이나 흙집에서 살고 싶어하는 사람들이 많습니다 It means "Nowadays, a lot of people want to live in tree house and earth house." Am I right? an i am confused... 나무집이(나) <-- 사람들(이) <--- what is the meaning of 나 & 이? are they optional ? Thanks in advance!