牛奶是含有丰富钙的食物之一。

Niúnǎi shì hán yǒu fēngfù gài de shíwù zhī yī.

Milk is one of the foods rich in calcium.

钙在人体中起着重要的作用。

Gài zài réntǐ zhōng qǐzhe zhòngyào de zuòyòng.

Calcium plays a crucial role in the human body.

补充足够的钙对儿童发育很重要。

Bǔchōng zúgòu de gài duì értóng fāyù hěn zhòngyào.

Adequate calcium supplementation is essential for children's development.