If you are asking about verb + 'ing' or 'ed' when used as adjectives expressing feeling e.g. boring/bored and how to understand the difference in meaning, I usually ask my students to think about the following sentences -
1. I was very excited when my father told me we were going to Disneyland.
2. Disneyland is a very exciting place.
Then I ask, 'Which sentence is about how I felt?' Students usually have no problem in identifying the first sentence. After this I ask, 'Which sentence describes Disneyland?' Again students have no problem in identifying the second sentence.
We then look at and answer similar questions about other sentence pairs such as:
3. The film was boring.
4. I was bored because the film was too long.
Finally, I tell them that 'ing' is what makes them feel 'ed' and that 'ed' is an emotion in their 'eds' (heads).