Simbo has been mining here for the past two years.

VOA: standard.2010.04.22

I've been here in MIT for thirty years, and in the early nineties I taught the large freshmen physics course, and electromagnetism.

我麻省理工工作三十年了，在上世纪九十年代初,我就开始给大一新生上物理课，以及电磁学。

麻省理工公开课 - 媒体、教育、市场课程节选

Many businesses that have been here for like 30, 40 years are being driven out.

很多在这儿已经有三四十年的商家都被挤走了。

纽约的负面变化 - SpeakingMax英语口语达人

I've been teaching here at Yale for ten years now.

已在耶鲁任教十年。

耶鲁公开课 - 新约课程节选