A dentist called Peabody became the first person to add soap to toothpowder in 1824 and chalk was added in the 1850s by John Harris.

1824年皮博迪医生首次在牙粉中添加皂粉；19世纪50年代约翰·哈里斯在牙粉中添加了白垩。

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John: Hello, My name's John Harris.

约翰：你好，我的名字叫约翰·哈里斯。

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John Harris, M. D., is a professor of surgery.

约翰·哈里斯，医学博士，一名外科教授。

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Mr. JOHN HARRIS (Editor in Chief, The Politico): Hey, glad to be back.

NPR: It's Election Day in San Francisco

Hillary Clinton failed to snag an emphatic win in Indiana, Politico.com editor John Harris says, her candidacy is mathematically over.

NPR: Analysis: Clinton Lacks Clear Path to Victory

We'll check in with John Harris of Politico.com, as well as the BPP's very own Monday Morning Quarterback, Bill Wolff.

NPR: Democrats Seek Sun as GOP Heads for Florida