You don't have many choices: as far as I know, you can go through either NYC (or New Jersey), Detroit or Chicago, and there is really no time to get out of the terminals anyway, security checks are quite painful in the States.
Time permitting, consider Seattle or San Fran. These two cities are not as big as NYC or LA, but have a lot of offer. Chicago is also fun, but it can get very very cold in winter (it has the nickname Windy City).
最初由 olush 发布 经美国转机回北京,走哪个城市呀?
城市可以选吗?
if yes,哪个城市好玩呀?可以中途趁机逛逛?
Maybe depending on the airline, few years ago, I stopped at San Francisco for three days and did not pay additional money. But last September I stopped at SF for three days again, I paid $100.