chronic = lasting a long time /recurring often
Last winter I had chronic bronchitis and ended up in hospital for 3 days.
Bronchitis is a noun for an inflammation of the mucous membrane in the bronchial tubes. Example sentence: My bronchitis was so bad that my boss didn't recognize my voice when I called in sick.
Cancer is a chronic disease.
The dreadful secret of the murder is a chronic mystery.
Infection of the bronchi would be bronchitis, while pneumonia is a disease which affects the lungs.
I have chronic pain in my hands every day. I have Chronic Bronchidas, i get it three times a year.
I am not writing a sentence using that word.
I can give you a sentence using the word galaxy.
a sentence using the word endotracheal
This is a sentence using the word aviator.
Children with chronic respiratory problems should avoid exposure to secondhand smoke.
I am saying a sentence using the word collagen.
This is a sentence using the word monomer. :P