amazing是指“（物）令人惊异的，使人惊愕不已的”

而amazed则是“（人）感到惊异的”，使用对象不同。

eg:I'm amazed to see such an amazing scene.

正如interesting是“有趣的，让人感兴趣的”而interested是“（人）感兴趣的”一样。

eg:It's such an interesting story that I am interested in it.

The -ing form expresses the quality of the experience itself: a circus is amazing, a long journey is tiring, an adventure movie is exciting.

The -ed form is the condition of the experiencer: I am amazed by the circus, I am tired from the journey, I am excited after seeing the movie.

An easy way to remember:

The thing is -ing, and -ed is me.