现在是中午十二点。

Xiànzài shì zhōngwǔ shí'èr diǎn.

It is twelve noon right now.

你中午在家吗？

Nǐ zhōngwǔ zài jiā ma?

Are you at home at noon?

你们中午吃了什么?

Nǐmen zhōngwǔ chī le shénme?

What did you eat at noon?