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All wealth is the product of labor.

Science should serve humanity, not the other way around.

The best biographies are those that make the reader feel they have met the subject in person.

The editor's job is to make the director's vision come to life.

小于給定數(shù)的素?cái)?shù)個(gè)數(shù)是該數(shù)的一個(gè)函數(shù)。