1. A swallowing test apparatus comprising: a laryngeal part displacement detection apparatus configured to detect a distance between two positions located laterally at a laryngeal part of a patient; a swallowing sound detection apparatus configured to detect a swallowing sound of the patient during swallowing; a processing apparatus configured to generate a waveform representing the distance of the two positions at the laryngeal part generated based on a signal obtained from the laryngeal part displacement detection apparatus, and a waveform representing the swallowing sound generated based on a signal obtained from the swallowing sound detection apparatus; a display configured to display the distance waveform and the swallowing sound waveform in response to the processing apparatus generating the distance waveform and the swallowing sound waveform; and an operation apparatus which is to be operated by the patient or a person who examines the patient when swallowing, the processing apparatus being configured to: detect a peak time of the swallowing sound when the swallowing sound is at maximum based on the signal obtained from the swallowing sound detection apparatus, and calculate an amount of characteristics of the swallowing based on at least one of a time interval between a time when the operation apparatus is operated and the peak time of the swallowing sound, a time when the distance between the two positions at the laryngeal part is at minimum before the peak time of the swallowing sound, and a time when the distance between the two positions at the laryngeal part is at minimum after the peak time of the swallowing sound, wherein the display is furthered configured to display the calculated amount of characteristics of the swallowing.