Because all toothbrushes wear out, dentists recommend replacing them every three to four months.

因为所有的牙刷用坏了，取代它们牙医建议每三至四个月。

youdao

Because all toothbrushes wear out, dentists recommend replacing them every three to four months.

因为所有的牙刷用坏了，取代它们牙医建议每三至四个月。

youdao