Grandma Smith's Crochet - "Debbie" pillowcase lace

DMC cotton #30, steel crochet hook size 10

R1: ch 17, turn

R2: in 9^th ch from hook (2 tr, ch 1, 2 tr), sk 3 ch, in next ch (2 tr, ch 1, 2 tr), sk 3 ch, 1 tr in next ch, ch 5, turn

R3: (in ch-1 sp (2 tr, ch 1, 2 tr) 2 times, 1 tr in top of ch-5, ch 5, turn

Repeat R3 for the length desired.