Today I've learned English language from "English Vocabulary in Use Book" of Unit 6 and the subject is "Health and illness".
It says that:
"Be in hospital" means you are ill, you are a patient. But
"Be in a hospital" just mean you are visiting someone.
wow! Both of these sentences they have so much difference of the meaning. Just because of in the sentences they have or have a letter "a".
Learning English is not easy.