回复：8老师，再问遍旅游签证过期，朋友去加拿大旅游后，

30天内您说可以再回美国。 请问我查到有人说只能走陆路， 不能飞机回美， 是这样吗？

-No such limitation. But some airlines may not understand this rule and thus, may not allow you to board the plane. So, you may print out the USCIS or CBP docuements about this rule.

See these websites:

http://www.trackitt.com/canada-discussion-forums/landing-in-canada/679067371/automatic-revalidation-to-enter-us

https://help.cbp.gov/app/answers/detail/a_id/1218/~/automatic-revalidation-for-certain-temporary-visitors

http://www.cbp.gov/linkhandler/cgov/travel/inspections_carriers_facilities/clp/bulletins/auto_reva.ctt/auto_reva.pdf

 

出境的时候也不能交回I-94 （半年有效）卡，对吗？

-Correct. Show this I-94 to the CPB officer when you return to US from Canada.