when 1 row remains before sole measures 8-9-10 (12-14) cm work the last row, at the same time dec 1 dc each side = 4-4-6 (6-8) dc. sew sole to slipper edge to edge with neat sts.

This is all lower case. Can you fix that?
When 1 row remains before sole measures 8-9-10 (12-14) cm work the last row, AT THE SAME TIME dec 1 dc each side = 4-4-6 (6-8) dc. Sew sole to slipper edge to edge with neat sts.