Start on a shawl with tr/dc
ROW 1: Ch 5, work 1st ch as follows: 1 tr, ch 2 (=ch-space), 2 tr = 1st row, turn.
ROW 2: Ch 4, 1 tr in 1st tr, ch 2, in ch-space on prev row work 2 dc, ch 2, 2 dc (= 1 dc-group). Then ch 2 and 2 tr in 4th ch in beg of prev row, turn.
ROW 3: Make a sl st in 1st tr and a sl st in 1st ch-space, in the same ch-space work: ch 4, 1 tr, ch 2 and 2 dc. In next ch-space work: 2 dc, ch 2 and 2 dc (= 1 dc-group). In last ch-space work: 2 dc, ch 2, 2 tr, turn.
ROW 4: Ch 4, 1 tr in first tr, ch 2. In next ch-space work: * 2 dc, ch 2, 2 dc (= 1 dc-group). * Repeat *-* i next 2 ch-spaces. End row by working 2 tr in 4th ch in beg of prev row, turn.
ROW 5: Make a sl st in 1st tr and a sl st in 1st ch-space, in the same ch-space work: ch 4, 1 tr, ch 2 and 2 dc. In next ch-space work: * 2 dc, ch 2, 2 dc *. Repeat *-* in the next 3 ch-spaces. End row by working in last ch-space: 2 dc, ch 2 and 2 tr.
Continue repeating row 4 and 5, the number of dc-groups will inc with 2 on every even numbered row (6th, 8th and 10th row and so on). Continue until shawl has desired length and end with an uneven numbered row.