哪些情况下是不用冠词的，哪些情况是用冠词的

common phrases

We don't use an article in expressions with school, university, prison and hospital.

go to bed
go to work
go home
go to hospital
go to prison

but we use the if someone visting with schoo, university, prison and hospital.

My son has started school now. I went to the school to meet his teacher.
I went to the prison a lot when I was a social worker.

place names

We don't use an article for continents, most countries, cities, towns, lakes, mountains or universities.

Africa, Asia
India, China
New York, Moscow
Mount Everest
Cardiff University

Some countries are different. Country names with United have the.

the United Kingdom, the United States of America
the Bahamas

Seas and Oceans, mountain ranges and rivers have the:

the Atkabtic, the Pacific
the Andes
the Nile, the Amazon

University with of in the title also have the:

the University of Cape Town
the University of Tokyo