He appealed to his countrymen not to lose heart.

他呼吁同胞们不要灰心丧气。

《柯林斯英汉双解大词典》

He told his men not to lose heart, saying that they would soon discover gold mines.

他告诉手下人不要灰心，并说他们很快就会发现金矿的。

youdao

One should never lose his heart when he is in trouble, because adversity can always serve as a paving stone to success.

即便身处困境，也不该丧失信心，因为困境能够充当成功的铺路石。

youdao

He was afraid he would lose his heart if he was not able to sing like a woman.

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