He reached in his pocket and unfolded a sheet of paper and held it out to Dean.
She unfolded her legs and sat on the edge of the chair.
He unfolded his arms and tossed some coffee into the boiling water.
He unfolded a piece of parchment.
This is due to the fact that while young the turgidity and consequent growth are greater in the dorsal side of the leaf, so that it becomes rolled up. As it develops the maximum turgidity and growth change to its upper side, and so it becomes unfolded or expanded.