Nancy is a student.she is in school.这句话哪错了

Nancy is a student.She is at school.翻译：南希是学生,他在学校就读.虽然句子
She is in the school 也对,但意义上不同,他要表达的不一定是指在校就读,可以是指在校教书等的,根据上句语境Nancy is a student,这边应该用Nancy is a student.She is at school.
英语中月份的最标准的缩略形式
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