They are generally classified into three broad categories—stones, stony irons and irons.

它们通常被分为三大类——石头、陨铁石和铁。

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For discussion purposes, we can divide these payments into three broad categories.

为方便讨论起见，我们可将这些支出分为三大类。

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There are three broad categories of disabilities that require the use of assistive technologies.

主要有三大类残疾人需要使用适应性技术。

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They fall under three broad categories: mitigation, adaptation, and the innovation that makes mitigation and adaptation easier.

FORBES: Richard Alley on Challenges, Choices and Climate Change

There is an abundance of new books to help them answer that question, and they fall into three broad categories: the big picture, self-help and the inspirational success story.

ECONOMIST: Starting out

There are plenty of modern books to help them answer that question, but most of them fall into one of three broad categories: the strategic guide, a technology focus, or career advice.

FORBES: Here's the CIO Playbook for the Next 5 years