But behind all that confidence, I figure, must be some hard lessons learned.

但是我知道，在这所有的自信背后，都有一些深刻的教训。

youdao

Bound and determined to succeed, I maintained a positive attitude by noting that the hard lessons learned from failures can be incredibly valuable.

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The hard lessons learned in places like Tarawa and Guadalcanal served the U.S. well when Marines turned the tide of war in Korea years later by mounting a daring amphibious landing at Inchon, behind enemy lines.

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But the hard lessons were learned perfectly.

ECONOMIST: Elisabeth Schwarzkopf