I am on OPT with F1 visa right now. The company I am working for asks me to attend a conference in Canada for 3 to 4 days. I wonder whether I need to apply visa for entering US for this trip....
I came to US in Aug. 2000 with F1 and graduated in Nov. 2006 without changing my visa status during those years. My opt started in Dec. 06' and I got a job starting in Dec 06' after I got...