Once you get to Row 3--and you may already be doing this--they want you to do ONE single into a single, then TWO singles into the next single, then ONE again into the next single, then TWO..etc. So you don't do two singles into the single below every single time, but every other time.
If you are already doing that part right, sorry! Hard to tell via posts...
"My predominant feeling is one of gratitude. I have loved and been loved;I have been given much and I have given something in return...Above all, I have been a sentient being, a thinking animal, on this beautiful planet, and that in itself has been an enormous privilege and an adventure." O. Sacks