当然它是困难的，但是这是你们来到地球要面对的挑战。
Of course it is hard, but that is the challenge you came to Earth to face.
当然，挑战也可以指某些你必须面对的困难。
Of course, a challenge can also refer to something difficult that you must do.
面对这些挑战对年轻的国家是困难的。
Confronting these challenges was difficult for the young country.
感谢xx老师，他使我具备了在未来面对困难和挑战的信心。
Thank you, teacher xx. It is you that endowed me with confidence of...
感谢xx老师，他使我具备了在未来面对困难和挑战的信心。
Thank you, teacher xx. It is you that endowed me with confidence of...
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