Breakdown of Hoy hay menos gente en la biblioteca.
Questions & Answers about Hoy hay menos gente en la biblioteca.
Because hay is the form used to say that something exists or there is/there are somewhere.
- Hay gente en la biblioteca = there are people in the library.
- Está/están are used more for saying where a specific person or thing is:
- La profesora está en la biblioteca = the teacher is in the library.
- Los estudiantes están en la biblioteca = the students are in the library.
So in this sentence, the idea is not about specific people already identified, but about the existence/quantity of people there, so hay is the right choice.
Because hay is an impersonal form of haber. In this use, it does not change for singular and plural.
So Spanish says:
- Hay un libro = there is a book
- Hay dos libros = there are two books
- Hay menos gente = there are fewer people
This is very different from English, where there is and there are must agree with the noun.