We come cob-a-coaling for stuff for the fire
We've nowt in the cellar to make it burn higher.
So go into your scuttle, and fetch us a lump,
And we'll try to mak last line to rhyme (Ecky Thump!!)...

[SPOKEN by the whole crew]
Nigel - I like your verse, the first line starts brilliantly,
although the second line seems just a bit too long to fit the rhythm of the song.
The blank third line is a master stroke,
but I personally regard a bit of "dumpty-dumpty-dee" or maybe the odd "fol-de-rol" as being more "traditional".

When stuck in a challenge, for lines to a song.
Try looking at Mudcat - it doesn't take long.
You quickly may find a version or more.
And a Blicky or two will impress for the score...