K – knit stitches (example: K1 means to knit 1 stitch)
K1B – insert right needle, as if to knit, into the stitch below and then knit
P – purl stitches (example: P2 means to purl 2 stitches)
PULY+K1 – pick up the long yarn created by the K1B, slip the knit stitch as if to knit onto the right needle, put both stitches back onto the left needle and then knit both together