Unlike in the Americas, where metallurgy was a very late and limited development, Africans had iron from a relatively early date, developing ingenious furnaces to produce the high heat needed for production and to control the amount of air that reached the carbon and iron ore necessary for making iron. (50)

metallurgy /'mɛtəlɝdʒi/ n. 冶金 (术,学)

ingenious /ɪn'dʒinɪəs/ adj.

1(指人)善於用新 的或简单的方法解决复杂问题的，心灵手巧的;

2(指物件)设计独特而精巧的;

3(指主意)别出心裁的, 奇妙的

furnace /'fɝnɪs/ n. 熔炉

我是分界线，大家先自己分析哦。

(Unlike in the Americas), (where metallurgy was a very late and limited development), Africans had iron from a relatively early date, (developing ingenious furnaces) ( to produce the high heat needed for production) and (to control the amount of air)( that reached the carbon and iron ore) (necessary for making iron.)

分析：

修饰一：(Unlike in the Americas),介词短语

中文：不像在美洲

修饰二：(where metallurgy was a very late and limited development) ,从句

中文：冶金术发展非常晚而且有限

修饰三：(developing ingenious furnaces) ,非谓语动词托福口语时间

中文：发展了独特而精巧的熔炉

修饰四：(to produce the high heat neededfor production),非谓语动词

中文：它可产生冶铁所需要的高温

修饰五：(to control the amount of air) ,非谓语动词

中文：控制空气的数量

修饰六：( that reached the carbon and ironore) ，从句，修饰air

中文：接触碳和铁矿

修饰七：(necessary for making iron. ) ，形容词短语，修饰air

中文：对于冶铁是有必要的

主干：Africanshad iron from a relatively early date

参考翻译：

不像在美洲，那里冶金术发展非常晚而且有限，而非洲拥有铁比较早，他们发展了独特而精巧的熔炉，它可产生冶铁所需要的高温，并且控制接触碳和铁矿的空气用量以满足冶铁需要。

这个句子的主要修饰成分就是非谓语动词、介词短语以及从句，大家务必想清楚，每一个修饰成分修饰的是什么，才能看清楚这个句子的结构。

其实状语从句不是特别会影响大家对于句子的理解。