Sure you can. They'll be bulky, but the rest is bulky, I imagine. When you knit with multiple strands, you just treat each group as one stitch.
"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