Hello!
I was an undergraduate student on an F-1 visa in the US, I got my bachelor's degree last year (June 2016), and I'm in my OPT right now (I'm working full time). My opt will expire in July 2017. I already applied the graduate school and I will get my new i-20 very soon and I will begin my graduate study in September 2017. My F-1 visa was expired in 2014, but my old i-20 (from my undergraduate school) is not expired until August 2017. I have been in the US from 2014 and I never left the country. Can I stay in the US and go to my graduate school directly? Or should I leave the US and go back to my country to get a new F-1 visa for my graduate school? Thank you! Thank you very much!