回复：请问各位老师，F1的valid to DS是什么意思

各位老师，F1（I94）签证中valid to不是日期而是DS ( duration of status)是什么意思？
-It means you can stay in US legally until you finish your F-1 study (i.e. I-20 expires or you graduate, whichever comes first).

学校的I20是2年的。是不是F1也就是2年的？


这期间如果回国探亲是否要从新签？
-Check the F-1 visa stamp on the passport, and if it will expire when you reenter US, you need to get  a new visa. Otherwise, you can use that unexpired visa to enter US.