Final answer:
Primary sources are firsthand accounts or original evidence written by someone who directly witnessed or participated in the event or period being studied, such as letters, diaries, documents, photographs, or interviews.
Step-by-step explanation:
An article is considered a primary source if it was written by someone who directly witnessed or participated in the event or period being studied.
Primary sources provide firsthand accounts and original evidence, which can include letters, diaries, official documents, photographs, and interviews.
For example, a primary source for the American Revolution would be a letter written by a soldier who fought in the war or a newspaper article published during that time.
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