The Smithsonian's National Museum of American History in Washington,D.C., has one of the oldest known pairs of Levi's jeans in its collection.

VOA : special.2009.12.18

C So, that's the breakdown. And, the grade is C level, 50% and it's based upon a performance of 50% absolute.

这些就是分类，分数是，那就是基于成绩的。

固态化学导论课程节选 : 麻省理工公开课

which is one of the few museums in D.C. that actually isn't free because it's not a national museum.

那是特区里少有的几个收费博物馆之一，因为它不是国家博物馆。

SpeakingMax英语口语达人 : 大都会艺术博物馆

U.S.C.'s Office of International Services says the number of students this year is about seven thousand five hundred.

VOA : special.2009.03.19

We asked the Washington,D.C., arts blogger Bob Anthony how this summer's festival compared to those of past years.

VOA : special.2009.08.05