回複：請教從加拿大來美的朋友

From what I heard, it is not my personal experience, you can apply green card with TN but during a period you cannot leave USA. If you have H1B, there is no such restrain at all. As a Canadian, you can stay in US for 6 months every time you cross border, no visa needed(or it is B2?). You cannot work unless you have either TN or H1B.