A luc bat is a Vietnamese poetry form. It has lines of 6 and 8 syllables alternately. The last (sixth) syllable on the first line is to be rhymed on the sixth syllable of the second, while the sixth syllable of the second is to be rhymed with the sixth of the third which is then rhymed the sixth of the fourth and so on. Like this below
xxxxxa
xxxxxaxb
xxxxxb
xxxxxbxc
xxxxxc
xxxxxcxd
Etc.

A deeply ordinary fellow with an uneducated lay person’s interest in words

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