各位大侠！求救！

ycyi121UID: 179383

我在gter上看到很多关于最多提前多少天登陆美国的消息，可是大家众说不一，有说30天的有说45天的，到底是多少天啊？这关系到机票问题啊。有没有打电话到大使馆亲自询问的确切消息呢？急急急！

haimingshaoUID: 169613

When can I travel to the US?
According to Department of Homeland Security regulations all initial or beginning students may enter the US 30 days or less in advance of the start date of their course, as stated on the I-20 form. Please consider this date carefully when making your travel plans.

A student who wants to enter the U.S. earlier (more than 30 days prior to the course start date) must qualify for, and obtain a visitor visa. A prospective student notation will be shown on his/her visitor visa and the traveler will need to make the intent to study clear to the U.S. immigration inspector at port of entry. Before beginning any studies, he or she must obtain a change of classification, filing form I-506, Application for Change of Nonimmigrant Status, and also submit the required Form I-20 to the Department of Homeland Security office where the application is made. Please be aware that there is an additional fee of $140 for this process, and that one may not begin studies until the change of classification is approved.