[Nfb-krafters-korner] question about a pattern

[Lovette Yewchan]

Hi there. I am on the monthly dishcloth list and don't want to ask any more questions there as I did not feel I was heard well.
Anyway I have a line of the pattern and I am a little confused. 
Row 1:	 (RS) K1, *YIF, Sl 1 (KW), YIB, K1; Repeat from * across row, end with K1
I understand putting the yarn in frjom and slipping the stitch as if to knit but what happens to the yarn that was in front of the work as you slip that stitch?
I seemed to be making new stitches doing that and I am not sure that is what was meant.
Hope someone can help.
Lovette