Here is a poem from Songs of Flying Dragons composed by royal scholars to test the newly developed Hangul script; hence, it is the first sample of the Korean language written in Hangul.
The tree that strikes deep root
Is firm amidst the winds.
Its flowers are good,
Its fruits abundant.
The stream whose source is deep
Gushes fourth even in drought.
It forms a river
And gains the sea.
From Encyclopedia Britannica:
The most representative akchang (“words for songs”) is Yongbi ŏch’ŏn ka (1445–47; “Songs of Flying Dragons”), a cycle compiled in praise of the founding of the Yi dynasty. Korean poetry originally was meant to be sung, and its forms and styles reflect its melodic origins. The basis of its prosody is a line of alternating groups of three or four syllables, probably the most natural rhythm to the language.