By lubricating airways, our third class of ingredients, expectorants, aim to help improve coughing rather than eliminate it.

通过润滑呼吸道，第三类成分祛痰剂，旨在帮助缓解而非消除咳嗽。

STEP 2 Drink licorice tea. Licorice root is an expectorant that breaks up mucus in the nose and the lungs, so you'll breathe more easily.

喝草茶。草根是一种化痰剂，可以分解鼻腔和肺里粘液，这样呼吸就更容易。

Guaifenesin, the most common expectorant, is thought to hydrate mucus by upping fluid secretions in the respiratory tract, making it less sticky and easier to clear out.

愈创油醚是最常见祛痰剂，它被认为是通过增加呼吸道中液体分泌物来滋润粘液，使其不那么粘稠，更容易清除。