Rocks.<br>A bunch of waves went over the cliffs. The weathering started to take a toll. Some rocks began to fall. They made a splash in the waves. The rocks fell to the bottom of the ocean.
A dolphin swimming by caused the rocks to fall.
( z1 cause :ARG0 ( z2 dolphin :ARG0-of ( z3 swim :path ( z4 by ) ) ) :ARG1 ( z5 fall :ARG1 ( z6 rock ) ) )