She's four years his junior.

她比他小四岁。

《牛津词典》

He battled cancer for four years.

他同癌症斗争了四年。

《牛津词典》

He spent four years studying pharmacy.

他花了4年时间学习药剂学。

《柯林斯英汉双解大词典》

The law will require Americans to have health insurance, with a few exceptions, or pay a fine starting in four years.

VOA: special.2010.03.26

I would say absolutely. And I would say even I could notice over the past four years I feel and there is a different tenor.

我答案是肯定的，我想说,甚至我都能感受到过去四年里,学校氛围发生的变化。

普林斯顿公开课 - 人性课程节选

I thought London gives me enough to do for the next four years while I am studying to have a life.

我觉得在我学会在这里生活的时候，伦敦给予了我足够在未来四年里可以做的事情。

世界就是我的故乡 - SpeakingMax英语口语达人

Over the past four years, sub-Saharan Africa's growth rate has been around 6% a year.

ECONOMIST: America in Africa

But even Panama has seen its murder rate double in the past four years.

BBC: Central America��s shift in safety

Worldwide, sales of digital set-top boxes are expected to nearly triple in four years, to 96 million.

FORBES: Cruz control