HSK 4
Zhèngfǔ zhèngzài nǔlì gǎishàn chéngshì de shuǐzhì.
The government is working to improve the city's water quality.
HSK 7-9
Zhè tiáo hé de shuǐzhì hěn chà, bùnéng yǐnyòng.
The water quality of this river is very poor and it cannot be used for drinking.
HSK 7-9
Jiǎncè shuǐzhì shì bǎozhàng gōngzhòng jiànkāng de zhòngyào cuòshī.
Testing water quality is an important measure to protect public health.
