一打

yī dá bǐ

一打笔

a dozen of pens

qǐng gěi tā lái yī dá

请给她来一打。

Give her a dozen, please.

wǒ bù què dìng wǒ men shì fǒu hái yǒu yī dá bǐ jì běn

我不确定我们是否还有一打笔记本。

I'm not sure whether we have a dozen notebooks.

shè yǐng shī men yǐ jīng pāi guāng le yī dá jiāo juǎn

摄影师们已经拍光了一打胶卷。

The photographers had already shot a dozen rolls of film.