The offer of American graduate students should be notified to the admitted students by electronic admission notice at the earliest in late February and early March, but most of the admission notices were received before April 15. "4. 15" protocol is 1999. A number of universities in the United States jointly formulated and implemented for foreign students. The main content is: students who have received admission notices from many schools must decide which school you want to go to before April 15, otherwise all admission notices will be considered invalid. From April 15 to the beginning of May, you also have the opportunity to receive the admission notice (usually supplementary admission).