Adjectives with -ing and -ed

Most English adjectives that describe an emotional experience end in either -ing or -ed.

For instance, take the word interest:

  1. The book interests me. (verb)
  2. I’m interested in the book. (the experiencer, -ed)
  3. The book is interesting. (the source of the experience, -ing)

The experiencer takes an -ed adjective, while the source of the experience goes with an -ing adjective. Generally, inanimate objects can only take -ing.

Animate objects can take either -ing or -ed. Hence, a teacher could be boring if the students are about to fall asleep, or a teacher could be bored if they’ve already taught the same lesson a hundred times.

Looking at our example again:

  1. The book [source] interests [emotion] me [experiencer]
  2. [source] [to be] [emotion]+ing
  3. [experiencer] [to be] [emotion]+ed

If you’re not sure which form to use, rephrase your sentence with a verb instead of an adjective. The word order will always tell you whether the adjective should take -ed or -ing.