Knitting in back on ribbing

:doh: I have been knitting for some time but I have never come across this one. I am ribbing and the instruction says k2P2 in back of first row.
How in the world do I knit and Purl in BACK
any help out there???
Thanks
Betty

Is that the exact wording? Doesn’t make much sense, does it. :thinking: Could they mean in back of the stitch?