Hello, I am very happy to answer your question. The answer is as follows:

This sentence should be regarded as a famous saying, said by Chairman Mao.

From: At the end of September 1951, Mao Zedong received a delegation from Anhui to participate in the National Day. Among the members of the delegation was the young hero Ma Sanjie who crossed the river. Mao Zedong asked her about her study situation with concern and gave her a beautiful notebook with an inscription on the title page: Study hard and make progress every day. This eight-character inscription quickly spread throughout the country.

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