I need two dozen.

我只要两打。

youdao

I need two boxes of cereal, one loaf of bread, a can of tomato paste, a dozen eggs, and two pounds of meat.

我需要两盒儿麦片， 一块儿面包， 一罐儿番茄酱， 一打鸡蛋和两磅肉。

youdao

So I think you need a slightly broader education policy than just simply bringing back two dozen grammar schools.

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