要将“比例率”拼写成英语文案，可以结合“比例”和“比率”两个词。以下是一些例句和表达方式：

比例 （ratio）

The ratio of men to women in the class is 2:1.

The ratio of water to sugar in the recipe is 3:1.

比率 （proportion）

A proportion of the students passed the exam.

The proportion of the total area covered by the forest is 40%.

综合表达

The ratio of the two quantities is 1:2, which means that for every one part of the first quantity, there are two parts of the second quantity.

The proportion of the total population that is urban is increasing over time.

这些表达方式可以帮助你在不同的语境下准确地描述“比例率”的概念。