system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How is it that mucus can build up in your lungs and not cause you to drown?

It's probably a question for one of the many medical subs but I'm no doctor, and need "laymen accessible" responses.

Edit: I have a second question, (I'll make a new post if I have to.) Why does it seem like excessive or violent coughing damages your throat? 

Edit 2: Thanks for all the help everyone!
gpt
Actually you can. Pneumonia is the build up of fluid that can cause death and it would be technically drowning. Humans are tougher than we think though, we can survive on only part of our lungs and it might just be enough to survive until we can get healthy again.