The old thread on this subject has gotten WAY too long, so I'm starting it over. I'd also like to take this time to remind participants of the limerick form, as lately it's been drifting more into five-line poetry.

There are two essential components: syllables and rhyme scheme. These two elements are what makes a limerick a limerick.

A limerick is in the AABBA form. That means that the first two and last line rhyme with each other, as does the third and fourth line. So, 125 and 34 rhyme.

These two sets of lines are distinctive again in that the 125 set comprises three metrical feet (or 9 syllables), while the 34 set comprises two metrical feet (or 6 syllables). So, 125 is 9 syllables and 34 is 6.

To sum up:

-Lines 1, 2 and 5: Rhyme together, nine syllables/three metrical feet.
-Lines 3 and 4: Rhyme together, six syllables/two metrical feet.

I tried to include the Wikipedia page for those who are interested in more examples and links, but it won't let me because of how the page title is structured.

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To begin this new game, here's a first line:

There was a lightkeeper from Truro,