Sijo is the classic form of unrhymed poetry in Korea.
Sijo have three long lines. Each line varies between 14 and 16 syllables, with the middle line often the longest.
The first line states a theme, the second line counters it, and the third line resolves the poem.
I will break the back of this long, midwinter night,
Folding it double, cold beneath my spring quilt,
That I may draw out the night, should my love return.