I have 5 years F1 visa. but its expiring soon. i am currently studying Masters in one university. this is my second masters. during these years, i didnt have the opportunity to visit Nepal. Now, i am planning to visit Nepal during summer break. But, by the time i am planning to return to america in summer break, I will have just one more month of Visa. Will there be any problem having just one month of visa remaining at port of entry? I heard that F1 students should have at least  six months of visa to get re-entry to US. Is this just rumors? Is there any time frame like this? Please, help me!!!urgent