Here's are some two-line standard blues lyrics circa 1905 from Odum. The first batch are from:
8. PO' BOY LONG WAY FROM HOME
No need, O babe! try to throw me down,
A po' little boy jus' come to town.
I wish that ole engeneer wus dead.
Brought me 'way from my home.
Central gi' me long-distance phone.
Talk to my babe all night long.
If I die in State of Alabam',
Send my papa great long telegram.
10. FRISCO RAG-TIME
Even more disjointed and senseless is the song called, for convenience at the moment, "Frisco Rag-Time," "K. C," or any other railroad name that happens to be desired. The song may be sung by man or woman or by both. It is expected that the viewpoint of man be
indicated in the use of woman as the object, and woman's viewpoint
be indicated in the reference to man. Such is sometimes the case;
but usually the negro sings the song through, shifting from time to time from man to woman without so much as noticing the incongruity of meaning. In the verses which follow the scenes will be portrayed
with clear vision by the negro singer.
Got up in the mornin', couldn't keep from cryin', :|(three times)
Thinkin' 'bout that brown-skin man o' mine.
Yonder comes that lovin' man o' mine. : | (three times)
Comin' to pay his baby's fine.
Well, I begged the jedge to low' my baby's fine, : | (three times)
Said de jedge done fine her, clerk dune wrote it down.
Couldn't pay dat fine, so taken her to de jail. : I (three times)
So she laid in jail back to de wall, : | (three times)
Dis brown-skin man cause of it all.
I : No need babe tryin' to ilimw me down, :](three times)
Cause I'm jx)' boy jus' come to town.
I: Hun if you don't want me, please don't dog me 'roun,(three times)
Give me this money, sho' will leave this town.
I : Ain't no use tryin' to send me 'roun'. :| (three times)
I got plenty money to pay my fine.
As WC Handy commented, at some point the blues were shortened to two repeats, fitting the standard 12 bar pattern which became popular less than ten years later,