Do you mean like a travelling cable? You'd slip two knits to a cable needle and hold in front, purl one from the left needle and then knit the two from the cable needle.
"Trust the pattern!"
Time flies like an arrow, but fruit flies like a banana.
Hop aboard while we follow the cloud-covered van of knitting harmony, man!! Woooo!! --Hedgehog
IngridKH on Ravelry