1) Curved 2) Curving 3) Hard to get a grip on 4) Hard to grasp 5) Long and sinuous 6) Long, sinuous, and slippery 7) Long, slippery and sinuous 8) Sinuous and slippery 9) Slippery 10) Slippery and sinuous 11) Slithery 12) Thin and slippery 13) Thin and wriggly 1) Curved 2) Curving 3) Slim 
[adj] - resembling an eel in being long and thin and sinuous
adjective resembling an eel in being long and thin and sinuous