to make someone feel annoyed or less confident because they cannot achieve what they want

It frustrates me that I'm not able to put any of my ideas into practice. 我的任何想法都无法付诸实践，这让我很灰心。

to prevent the plans or efforts of someone or something from being achieved

The continuing civil war is frustrating the efforts of relief agencies. 持续的内战使救济机构的努力受挫。