Verse 1 0:06-0:20
Verse 2 0:26-0:40
Comments: In many ways, "Polythene Pam" could be the first half of a complete song - its structure, with the intro/tag, verses, and solo, matches rather nicely with the first halves of previous Beatles songs. If it were to be an independent track, however, it would need the addition of a middle 8 (and probably a middle 8 on the long side in terms of duration - more like 16 bars instead of 8), likely immediately after the solo, which could then proceed to a third and final verse, before concluding with a coda.
In any case, it's not an independent track, and it doesn't have a middle 8, and because of its nature as part of a medley, it really doesn't need one. Its structural function is very much tied in with  "Mean Mr. Mustard" - they could be thought of as pairs, both being Lennon fragments, and both being in E major.