他们学习很认真并且严格要求自己。

They studied hard. They were both strict with themselves.

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他们通常对学习很认真，对考试得低分感到失望。

They are normally serious about learning and feel disappointed with low grades on tests and exams.

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虽然聪明的小孩可能没有必要在学习简单的低年级功课时刻苦努力，但是当课程加深后他们会学地很费力而且成绩很差，原因在于他们并没有认真去学。

Although smart kids may not need to work hard in the lower grades, when the work is easy, they may struggle and perform poorly when the work gets harder because they do not make the effort to learn.

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