求翻译：某学生托福79分，在美国却因为听不懂教授上课内容,读不懂教授提供的书目，规定时间完不成论文而成绩直线下降。是什么意思？

TOEFL 79 points a student in the United States but because professors do not understand the contents of class, professors can not read the books, papers and able to fulfill the specified time performance plummeted.

One of his students, a TOEFL score of 79 in the United States, however, because we don't understand what they didn't understand professors to teach content provided by Professor, reading books and papers that cannot be completed in time performance plummet.

Some student receives help for 79 minutes, in US because cannot understand professor to attend class actually the content, but cannot read the booklist which professor provides, the scheduled time cannot complete the paper the result straight line to drop.

A student of TOEFL 79, in the United States but because the professor could not understand the lesson content, provided by the Professor can't read books, time finish paper scores plummet.

79 fen of TOEFL for one student, but can not understand the content that a professor has a class in U.S.A., can not understand the book-list that a professor offered, stipulated time can not finish the thesis and the achievement plummets.