How nice question! --Üzgün is used for living beings and there is a logic behind. Üzgün comes from the verb "üzülmek" - to become/get/be sad So we can not use it for nonliving things as they have no chance to get sad. --For the word "acıklı" we have another alternative "üzücü" üzmek - to make sad / to sadden üzücü, acıklı - the thing that makes you sad (can't be a living thing) acı - bitter (both for food and almost anything) *I would use the word acıklı especially for weepy songs, movies or sad events. It gives a bit more sad feeling than üzücü when you hear. Bu film çok acıklı. This movie is so sad. Bu durum gerçekten çok üzücü/acıklı. This situation is really so sad. Ben çok üzgünüm/üzülüyorum. I am feeling so sad. Çocuk üzgün gözlerle bakıyor. The kid is looking with sad eyes. Böyle üzücü sözler söyleme. Don't tell me such sad words. Bu kanalda hep üzücü/acıklı haberler var, izlemek istemiyorum. There are always sad news on this channel, I don't want to watch. --Please let me know if there is something that you want me to explain more. Good luck!