A person s hand holding piece of white chalk is positioned against clean empty green chalkboard the image symbolizes education 向量例证 a person s hand holding piece of white chalk is positioned against clean empty green chalkboard the image symbolizes education
An older adult hands a book titled world history to a younger person both wearing dark sweaters the setting is a classroom with a 向量例证 an older adult hands a book titled world history to a younger person both wearing dark sweaters the setting is a classroom with a
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