我对自己的进步缓慢感到非常沮丧。

I'm very ___frustrated at my lack of progress.

球迷们对他们本赛季缺乏成功感到沮丧。

Fans are ___frustrated by their lack of success this season.

然而，让我们非常沮丧的是，本月末我们没有机会参加考试。

What, however, made us very ___frustrated was that there was no opportunity for us to take an exam at the end of this month.