肺

hai chikara ga suくない kara nagaku hassirenai

Because I don't have much lung capacity, I can't run long distances.

haien o wabitta koto ga aru kara tabako wa suwanai

I've had pneumonia before, so I don't smoke.

kitsuen wa hai ni shinkoku na damēji o ataeru koto ga igakuteki ni shōmei sareteiru.

It has been medically proven that smoking causes serious damage to the lungs.