They used information gathered over a period of 20 years, until 2003, in the Framingham Heart Study.

VOA: special.2009.01.21

Clearly, important information is to be conveyed to students from people who settle in the fields for a long period of time.

显然，对某个领域,进行长时间研究的学者,会将重要的信息,传达给学生。

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