2 sentences

1. 海口处的河水往往咸淡混合。

   hǎi​kǒu chù de hé​shuǐ wǎng​wǎng xián dàn hùn​hé.

   The water at the river mouth is often brackish.

   Source: Dong Chinese Dictionary

2. 这座城市自古以来就是一个商贾云集的海口。

   zhè zuò chéng​shì zì​gǔ​yǐ​lái jiù shì yī gè shāng​gǔ yún​jí de hǎi​kǒu.

   Since ancient times, this city has been a seaport where merchants gather.

   Source: Dong Chinese Dictionary