sentences: level is used for absorbing sound matter by animal
docs: animal_ear is ear. deaf_animal is hearing_impaired_thing. animal_ear is organism_part. sound_frequency is sensory_information. animal_noise is audible_sound. animal_part_region_function is reifiable_function. bleating is animal_noise. herd_animal is air_breathing_vertebrate. ear_protection_gear is physical_impact_buffer. animal_utterance is audible_sound.