Andres Y Cecilia son los hijos de Javier
These sentences can be complete in the following way:
1) Nadie.- this would mean that you do not know anyone.
2) Ningún- it makes reference to the book. you do not have a book
3) nunca. This means that you do not do that activity. you never do it
4) ni. not having one thing nor the other.
5) nada. this means that the table is empty- nothing on it.
At 2:45pm, it would be la clase de música
As Spain began to colonize more and more countries those countries began to develop slang which then resulted in the slang being an everyday thing so then it became part of the language so thats why every spanish speaking country speaks differently.