On this week's episode:
1. Something does not exist where it should
Falta seguridad en este barrio.
There is a lack of security in this neighborhood.
I am $3 short of buying the book I need.
Me faltan 3 dólares para comprar el libro que necesito
2. To miss an important obligation
Hoy falté a la escuela
I missed school today
3. When something is missing from where it usually is
Me falta un libro en el estante
I'm missing a book on the shelf
4. Failure to fulfil a promise or complete what is expected
He promised to call me yesterday, but he broke his word.
Me prometió que me llamaría ayer, pero faltó a su palabra.
5. When something could improve something else if it was there
The soup is lacking salt (to the soup salt is missing).
A la sopa le falta sal.
HACER FALTA
1. hacer falta = to be necessary
a. Para dominar un arte, hace falta esfuerzo y dedicación.
To master an art, hard work and dedication are needed/necessary.