这三个词都带有失望、沮丧的含义，但是各自的用法却不同。

disappointment是名词，通常用词组“to one's disappointment”搭配使用表示“令某人极为失望的是”.

例句：To their great disappointment,the zoo was closed when they got there.他们到动物园时已经关门了，真是太令人失望了。

disappointing是形容词，表示“令人失望的，令人扫兴的”，主语应该是一个客观的事实。

例句：The game result is so disappointing. 比赛结果真叫人扫兴。

disappointed是形容词，表示“感到失望的”，主语通常是一个人。

例句：I feel so disappointed. 我感到很失望。

大家学会了么？可以在下方评论处用这三个词各造一个句子，例如：

To children's disappointment,the football game was cancelled because of the weather.令孩子们失望的是，足球赛由于天气原因被取消了。

The concert was cancelled at the last minute.How disappointing!演唱会在最后时刻取消了。真叫人扫兴！

I was so disappointed when I realized the concert was cancelled at the last minute.演唱会在最后时刻取消了，我感到很失望。

或者你有更好的用法也可以写在下方评论处，大家一起交流一起学习！