One of the manuscripts I looked at this summer, Maidstone A.xiii, has the lyric "Man mei longe him liues wene." I should say that it's actually a song lyric: the Maidstone witness has music above it.
Here are the words, edited by Carleton Brown, English Lyrics of the Thirteenth Century.
Man mei longe him liues wene
ac ofte him liyet þe wreinch
fair weder ofte him went to rene
an ferliche maket is blench .
Here's my ad hoc translation:
Man may imagine a long life for himself
but often a trick awaits him
his fair weather often turns to rain
and filthy turns the sunshine .
The song lyric is edited by Brown as having short octosyllabic lines, but such breaks are not evident in the copy text. I think I'd favour longer lines, perhaps with spaces between line sections to emphasize the line-internal rhymes. Still, I guess the rhymes indicate what we would now think of as poetic line breaks, in English poetry, anyway.
There is however a punctus after “blench,” suggesting that it might be good to pause the stanza here. This seems important given the sense of the phrase. "Fair weather often turns to rain / and dreadful turns the sunshine” is a nice chiasmus which plays upon the similar-sounding “fair” and “ferliche.” ("Ferliche" could be suddenly, as well as dreadfully--here I used "filthy" just because it sounds better.)
I see a similar kind of wordplay going on with "longe" and "wene"--I think the sense is "long life" but there is a play on longing for or yearning for a long life. There is also a distinctive Anglo-Saxon alliterative echo here: “man mei” is echoed by “maket,” and the “w” of wene, wreinch, and weder also echo throughout the phrase. The other repeating sound is “l” (longe, liues, liyet, blench).
I don’t usually think of alliterative poetry as having been sung; shame on me. Maybe it's because in English studies my focus is so often on the words, to the exclusion of all else. I haven't seen any articles on the music of this song, and it's not in DIAMM from what I can see.
This song is indexed as NIMEV 2070.