Pure Tone Audiometry (PTA) : Shows dip at 2,000Hz, called " Carhart's notch" .

表现为 2000Hz 时，听力下降，称为“卡哈切迹”。

19. When it is struck, a tuning fork produces an almost pure tone, retaining its pitch over a long period of time.

19。音叉被敲击时，产生几乎纯质的音调，其音量经久不衰。

The flowers also are peculiarly beautiful and effective; the female dark rich purple, the male blue, of so fine and pure a tone.

这些花也特别美丽和有效。 雌性深紫色， 雄性蓝色，色调如此精致纯净。