dishearten|disheartened|disheartening

连续的失败开始让运动员们灰心丧气。

The repeated failures started to ___dishearten the athletes.

不断的失败使他灰心丧气。

Constant failures ___disheartened him.

看到自己的努力没有取得任何进展，真的很让人灰心。

It was ___disheartening to see no progress despite all the hard work.