for the last few years和 in the last few years的区别

1、for the lastfew years 表示“近几年以来”,多与完成时态连用,含持续时间的意思.


The controversy has waged for the last few years.近几年以来,论战一直在进行.
After having made his pile by working in industry for the last few years, he moved to the country and bought a farm. 最近几年以来,他在工业方面干到发财之后搬到乡村,买下一个农场.


2、in the lastfew years 有两层含义


1）与将来时连用表示“在最近几年以后”,含后续时间的意思,如：


In the last few years we may no longer have a monarchy.最近几年后,君主政体可能将不复存在.
In the last years you'll have no bloody things. 这几年后,你们不会再有任何该死的东西了.




2）与和一般时态连用表示“在近几年中”,含有不外延时间的意思,如：


They have amassed a fortune in the last few years.他们在近几年的时间里就聚集了一笔财富.

看完张达人老师的回答了，我也完善一下答案：
【in】
1.在某段时间内
in the 18th century在十八世纪 in spring 在春天
In the last few years, this art has made a big leap. 近几年来, 这一艺术有了新的跃进.
I'm getting forgetful in my old...

一般来说，for...用于完成时态，in...用于一般过去时态。