"His lips curled into a smile."
"Her legs had walked twenty miles that day."
Oh, those autonomous body parts. The trouble is, they sound so plausible when you write them, so risible when someone else reads them. "Did she pick up her eyes and put them back in?" they say. "And where was the rest of her body? Back home, reading a book by the fire I expect."
Eyes cause particular problems, forever dropping onto things or even flashing across rooms, conjuring up images of ocular streakers. Substitute 'gaze' if you must - her gaze dropped, his gaze flashed across the room - or use a verb - she stared at the floor, he glanced across the room. With the other body parts, it's better to use an active verb for the whole character - he smiled, she'd walked twenty miles that day.
It may seem a small point but, let's face it, you want readers to laugh at your intentional funny bits not the unintentional ones. The only autonomous body part allowed in fiction should be the grin on the face of the Cheshire Cat.
NEW!!! I've finally got round to organising some course dates....
How to WRITE a Novel: London 3rd May/Birmingham 7th May/
Oxford 8th May/Exeter 21st May/Bath 12th June
How to SELL a Novel: London 24th May/Exeter 4th June/
Bath 3rd July Details are on my website