子來美國讀私立小學，學校8月底開學。我希望他6月來適應環境。 F-1 簽證，隻能提前一個月入境。
他去年以B-2來過，B-2簽證還未過期。可否
4月國內先申請F-1，6月以現有的B-2進來，
-If he applies for F-1 visa, the VO will revoke his B-2 visa when approving his F-1 visa. His passport can not have two kind of valid visas at the same time.
7月底去墨西哥旅遊一趟，用F-1簽證過來
-The US Consulate in Mexico does not allow him to apply for the F-1 visa if he uses B2 visa to enter US. He may go to Canada to apply for the F-1 visa, but if the F-1 visa application is denied in Canada, he has to go back to China directly from Canada.
可行否？風險大嗎？
謝老師的答複！
