Many of my teeth have become very sensitive at the gumline.

我的许多牙齿的牙龈边缘变得十分敏感。

youdao

Slide floss up and down against the tooth surface and under the gumline.

幻灯片牙线上下对牙齿表面和牙龈线下。

youdao

Slide floss up and down against the tooth surface and under the gumline.

幻灯片牙线上下对牙齿表面和牙龈线下。

youdao