There is nothing wrong with the students ear; the problem is the way third tone has been taught for decades, as if it had a rising tail.

Except for an exceptional isolated circumstance, the third tone does not go down and then up again, and it should not be called the “dipping tone.” It should be called the “low tone,” because it is spoken in the lowest part of your vocal range. It is most often short and flat.

Tones should not be taught in isolation, but always in combination with other tones. See our episode about the twenty combinations.