This article is from the FAQ, by with numerous contributions by others.
Foreign students are permitted to stay in the U.S. for the entire period of
enrollment in an academic program plus any period of authorized practical
training and a 60-day grace period to depart the U.S. The whole period is
normally referred to as duration of status and is noted on the I-94 as
D/S. The student must complete the academic program prior to the date of
expiration listed by the designated school official on the I-20AB (a form
issued by the school). Do note, however, that you must carry a full time
course load (except if you are in your last semester of study). See the
following answer.
 
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