在视频中，钟南山医生在本学期的第一课上鼓励青少年努力学习。

On video, Doctor Zhong Nanshan encouraged teenagers to study hard in the first lesson of this term.

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还有些同学我知道你们是很努力学习的，可是每次听力测试和辩论都表现平平，甚至处于相对劣势中，但是我想对你们说：不要紧的！

I know some of you have been working extremely hard, but did not perform well in each listening test and debating practice.

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他必须努力学习以保持他在同学中的领先地位。

He had to work hard to remain ahead of his classmates.

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