HSK 5
Gànxìbāo yánjiū yǒu hěn dà de qiánjǐng.
Stem cell research has great prospects.
HSK 6
Hóngxìbāo fùzé yùnshū yǎngqì.
Red blood cells are responsible for transporting oxygen.
HSK 7-9
Réntǐ yóu wúshù gè xìbāo zǔchéng.
The human body is made up of countless cells.