(a) We often use the following nouns without an article when we think about the main purpose of the place.
School, University, College, Hospital, Prison, Church, Bed
e.g. Maria goes to school every morning. (main purpose of the school is to study)
The school was painted last night.
I think I 'll go to bed tonight. ( main purpose is to sleep)
There are shoes under the bed.
Mr. Wood has gone into hospital. (main purpose is to take medical treament)
Sarah met Simon outside the hospital.
(b) We normally use work and home without article
e.g. What time do you usually go to work ?
Are you staying at home this evening?
2. Means of transport
We use by car/bus/train/plane etc, without an article.
e.g. I usually go to school by car.
We went to Rome by train.
I came back home on foot.
We do not normally use an article with the names of meals.
e.g. What time do you ususally have breakfast ?
What would you like to have dinner ?
But we use the when we specify
e.g. I enjoy the dinner we had last night.
We can also say a/an when there is an adjective before breakfast/ lunch/dinner.
e.g. They had a large breakfast.
Reference; The Heinemann ELT, English Grammar, An Intermediate Reference and