Understanding pattern

Hi -

I am wondering how to knit the following:

[sl1 wyif] three times, *k3, [sl1 wyif] three times; rep from *

I understand to slip the stitch purl-wise - do I do that three times in a row, then knit 3?

Thanks in advance for your help.

Yes, that’s right. Slip 3sts purlwise with yarn in front, then the repeat is (k3, [sl 1 wyif] 3 tunes).
What pattern are you following? Can you give us a name?

Thanks for your help!! I really appreciate it. It is called a Wide Horizontal Herringbone stitch from this book: