"그립다. 긴 머리 일년 전으로 돌아가고 싶다" sounds fine and not particularly formal to me. It however doesn't say "I miss my long hair" but rather "I miss my long hair days", but it sounds better to me this way :-) You can also use 그리워 and 싶어 instead of the ~다 forms to make it less formal. But 그립다 and 싶다 are also often used in this kind of contexts to express directness, so nothing wrong with them. Other possibilities (still using "long hair days"): - 일년 전 긴 머리 했을 때가 그립다. 그때로 돌아가고 싶어. - 긴 머리 했던 때가 그립다. 일년 전으로 돌아가고 싶어져. * "하다" in "긴 머리(를) 하다" is like "wear". Ex: 정장을 하다 = Dress formally. 매니큐어를 하다 = Wear nail polish. * 싶어져 expresses the rise of the sentiment rather than an existing state, "I feel a (new) longing for...", etc.