There is a lot of confusion for non-native speakers about which form of an adjective to use: the «-ed» or «-ing» form. English has many such adjectives that describe feelings. I have frequently heard students say something like, «I was boring, so I left the party». However, if YOU are boring, that means that you cause others to feel bored, you aren’t an interesting person. So I thought I would address this topic.
We use the -ing form to describe something that causes a feeling in us:
It was a boring movie.
The movie was boring.
That was a really interesting book with a surprising ending!
The -ed ending is used to describe how we’re affected by something, how we feel about it:
If I watch a boring movie, I’m bored.
If I read an interesting book with a surprising ending, I’m interested and surprised.
However, be aware that people can cause feelings within us.
If Jay is a boring person, I feel bored around him. Jay is boring.
We see this -ed/-ing pattern with many adjectives. Notice that they are are based on verbs: bore, interest, excite, confuse, surprise, tire, annoy, frighten, amuse, embarrass, etc.