Posted: Wed Aug 28, 2019 8:58pm
Hiya Lee
This is most definitely NOT the easiest question :-D - “por” can also mean “by” or “through” and “para” can also mean “by” depending on context.
“Por” is used to talk about movement, modes and means of travel and communication, exchanges, duration and motivation amongst other things e.g.
Communication and Travel:
La contacté por correo - I contacted her by mail
Viajé por Francia y España - I travelled through France and Spain
¿Quieres pasar por el parque? - do you want to go through the park?
Exchanges:
Te cambio mi manzana por tu sándwich - I’ll swap my Apple for your sandwich
Duration:
Tengo que trabajar por ocho horas hoy - I have to work for 8 hours today
¿Dormiste por 12 horas? - you slept for 12 hours?
Motivation:
Trabajo por ti, porque te quiero cuidar - I work for you because I want to take care of you
Para is used to talk about destinations, recipients, deadlines and goals e.g.
Destinations:
Salgo para Francia mañana - I leave for France tomorrow
¿Para dónde vas con tanta prisa? - where are you going in such a hurry?
Recipients:
Este regalo es para ti - this gift is for you
No, estos chocolates no son para los niños - no these chocolates are not for the children
Deadlines:
Necesito la presentación para el viernes - I need the presentation by Friday
Tengo que terminar esto para las ocho - I have to finish this by eight o’clock
Goals:
Él trabaja mucho para ganar más dinero - he works a lot in order to earn more money
Hago yoga para mantenerme en forma - I do yoga to keep fit
Hope this helps
Darío