一个英语问题：原句：I didn't work for twenty years ,为什么不是I haven't wor

那I haven't worked for twenty years?和I didn't work for twenty years ，有区别吗？是不是过去式也能用时间状语？例如：I have lived there since i come here .和I lived here since i come here.什么时候过去是能用时间状语，能不能多给我一些example?Thank you so much. 我二十年没有工作了可以翻译为I have twenty years of not working吗？那时我在网上翻译的，但总感觉挺别扭的，还有其他翻译吗