TASK DEFINITION: In this task, you are given a sentence which contains a motion and your task is to identify the physical entities involved in the motion. The input sentence can have more than one entity and also there is at least one entity that takes part in physical motion. There are two types of entities which are animate (beings that are alive) and inanimate entities (beings that are not alive).
PROBLEM:  The person next to her then piercing one ear followed by the other.

SOLUTION: person

PROBLEM:  The referee lets them know when to start and the sumos wrestle while the referee walks around the ring and monitors them.

SOLUTION: the sumos

PROBLEM:  The man then begins playing the piano while the camera captures his movements.

SOLUTION:
man