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》

Not to lose heart, when we are in trouble.

当我们遇到困难的时候，不要灰心。

youdao

We told him not to lose heart in times of difficulty.

我们告诉他在困难时别灰心。

youdao

And any argument between us would not cause me to lose heart or feel a sense of loss.

VOA: special.2010.07.11

If that bank says no to you, do not lose heart.

VOA: special.2010.07.18

This is not the time to lose heart.

ECONOMIST: The war in Afghanistan

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

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However, he said that according to recent census results, 59% of people still identified themselves as Christian, and believers should not lose heart.

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