ConceptNet
An encyclopedia of concept simulations that computers and humans can learn from.
An experimental project in machine learning.

drip
to fall slowly, drop by drop.

flap
to move up and down.

cover
to put something over or on something else.

stack
a pile of things, one on top of another.

crumble
break or fall apart into small fragments, especially over a period of time as part of a process of deterioration

meet
to come face-to-face with another person

crush
to damage something by squeezing it very hard.

cliff
the high, steep side of a mountain or rock.

sort
to arrange things into different types or groups.