1.footprint n.脚印

Perhaps you're trying to reduce your carbon footprint.
或许你是要减少你的碳足迹。

2.circle n.圆圈

The economy is stuck in a vicious circle.
国家的经济陷入了一个死循环。

3.revenue n.岁入，税收

Revenue at both yahoo and aol is steadily falling.
雅虎与美国在线的年收益也呈稳步下降趋势。

4.pile v.堆起；堆叠；放置

A worker throws a computer casing onto a pile.
一个工人将一个电脑外套扔到一个废物堆上。

5.investment n.投资，投资额；封锁

Trade and investment will be hurt.
贸易和投资将受到影响。