316. In 2007 the University of Wisconsin-Madison—one of the top five or so prestigious public universities—graduated 81% of its white students within six years, but only 56% of its blacks.

译文　在2007年，排名第五位左右的著名公立学校之一威斯康星大学麦迪逊分校，六年内白人学生的毕业率是81％，但是黑人学生的毕业率只有56％。

点睛　本句的主干是...the University of Wisconsin-Madison...graduated 81% of its white students..., but only 56% of its blacks。81% of its white students与but only后的56% of its blacks是并列关系。one of the top five or so prestigious public universities是the University of Wisconsin-Madison的同位语。

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