回複：一個關於F1 學生身份的問題

Based on the immigration law, the F1 student can not stay outside U.S. > 5 months. After an absence of more than five months, an F-1 student is no longer admissible to the U.S. as a “continuing student” and thus, the student has to get a new F1 visa with a new "initial" I-20 if he/she wants to be an F1 student.