You mean, how you say 'I don't know.' in Korean? If it is, 'I' means '나', - the place of 'I' is for subject, so a particle '-는' is automatically added. '나는' can be shortened to '난.' 'don't know' means '모르다(base form)' - between friends, '몰라' - when you say this to a person you don't know or to an older person than you, '몰라요' or '모릅니다' I don't know. - 나는(난) 몰라요. or 나는(난) 모릅니다. You don't have to say '나는(난).' Overall, '몰라요' is commonly used. '모릅니다' is used in a formal manner.

sorry I can"t speak English well Do you want it?? ?? don"t know 모르다 >> 몰라(요) know 알다

Oh! Now I get what you asked.. say 'mol-la-yo' for 'I don't know.' :-)