海水比淡水咸。
hǎishuǐ bǐ dànshuǐ xián 。
Seawater is saltier than freshwater.
我们去海边玩，海水很清澈。
wǒmen qù hǎibiān wán ， hǎishuǐ hěn qīngchè 。
We went to the seaside to play, and the seawater was very clear.
海水温度在夏天会上升。
hǎishuǐ wēndù zài xiàtiān huì shàngshēng 。
The temperature of seawater rises in the summer.