加拿大的国家公园票到美国可以用吗？
No. However, the pass is quite reasonable. $20 pass will be valid for 7 days for each National Park.
听说yellow stone不是很好玩, 是真的吗？
Personally, I like it. Landscape is much similar to Jasper. However, it has many more valcano scenic areas, which are quite unique.
还有个问题是：你们怎么不到las vegas? 还差500KM就到了
I intentionally avoided that area. Actually, I was only 200KM away of LV. I am a pretty much a nature guy. Man-made stuff is not my type. And be prepared for the crazy traffic in big US cities. Driving in Salt Lake City is already crazy enough. ;-)
By the way, I was on my own. No "你们".