Making a thumb gusset on a mitten

I was wondering if someone could tell me how to do the following.

K1, P1, increase 1 st in each of next 2 sts., k1, p1. Knit to end of round.

Does this mean that I knit 1 st, purl 1 st, then knit the increased st, knit the st you just make the new st in, knit the next increased st, then purl the st you just made the new st in? Or does it mean the following:

Knit 1 st, purl 1 st, knit the increased stitch and the stitch you made that stitch in, knit the increased stitch in the next stitch and the stitch you made that stitch in, then knit the next stitch and purl the one after that? Then knit to the end of the round.

Knit 1, purl 1, kfb (that’s the increase in a st) twice, k1 p1. If you don’t know how to knit into the front and back of a stitch, there’s a video on the Increases page.