试译：You can't fool me, for I lived here for six years.
这里的“之前”不一定要用 before 来翻译，句子中用一般过去时就行了。
我的理解是：“你蒙不了我”的意思是：你骗不了我。而You can't fool me，我读后的反应是：你不能骗我。这个意思和你蒙不了我的意思是不同的。所以，我觉得应改译为英语的习惯表达：You could have fooled me. 请看《朗文词典》的解释：
“我之前在这里住过六年”，不必想得过于复杂，可能弄巧成拙，简单翻译为：I have lived here before for six years.当然用过去式Ｉlived here for six years.也没问题。
1. We are very much in love with Wisconsin already as we have lived there before for 3 years and our moving back again certainly proves it.
2. Well I have been here before for one year and I was shy, waiting for people to talk to me...