There isn't a dog (no hay un perro)
There isn't a window (no hay una ventana)
There isn't a computer (no hay un ordenador)
There isn't a pen (no hay un bolígrafo)
There isn't a picture (no hay una foto)
There isn't a teacher ( no hay un profesor)
There isn't a book (no hay un libro)
There isn't a pencil (no hay un lápiz)
There isn't a girl (no hay una chica)
There isn't a boy (no hay un chico)