Hi there,
Do the following sentences mean the same?

1. Most students usually study hard to enter a university.
2. Most students usually study hard to enter universities.


3. Most students usually study hard to go to university.
4. Most students usually study hard to go to the university.
5. Most students usually study hard to go to universities.


6. Most students usually work very hard to study at the university.
7. Most students usually work very hard to study at universities.

Very thanks

peter