All the people were asked about their use of pesticides, chemical fluids and metals like iron.

VOA: special.2009.04.07

Because the earth is made of iron, heaven knows everything is made of the same stuff, all heavenly bodies.

因为地球是由铁构成的，上帝知道一切,世间万物是由同一东西组成的，即天体。

麻省理工公开课 - 固态化学导论课程节选

Seems very simple, but took Beethoven a long time to iron all this out and make this perfect melody, the prototypical melody in a way.

似乎很简单,但是花了贝多芬很长时间来琢磨,最后做出这段完美的旋律,这段典范旋律

耶鲁公开课 - 聆听音乐课程节选

Working in such a laundry was known as the eight-pound livelihood because a person had to lift an iron weighing almost four kilograms all day.

VOA: special.2010.03.03

First of all, iron weapons, not bronze ones.

首先,铁制的兵器,而非青铜的

耶鲁公开课 - 古希腊历史简介课程节选

Almost all cells need iron to grow.

VOA: standard.2010.08.05