1. Por or Para
Although the prepositions por and para may both be translated as for in English, they are not interchangeable in most cases. Each word has a distinctly different use in Spanish, as shown in the following slides.
Note that an infinitive is used when a verb comes
after por and para as well as after all prepositions.

2. Recipients or intended person(s)
Para
Para is very unidirectional and points forward toward a goal or destination, whether literal or figurative.
Para indicates:
Point of time or space (deadline) 1
by a certain time; to or toward a certain location
Destination or destiny 2
goal, intended purpose 3
Recipients or intended person(s) 4
Comparison (with a norm) 5
Purpose or goal (to, in order to)

3. Para 1 2 Destination, destiny Limit of time or space (deadline)
Mañana Juan sale para Madrid.
Tomorrow Juan is leaving for Madrid.
El rey sale para la conferencia mundial.
The king is leaving for the world conference. 2
Limit of time or space (deadline)
Debo llegar a la reunión para las 10:00, a más tardar.
I must arrive at the meeting by 10:00, at the latest.
Es necesario que terminemos el informe para el martes.
It is necessary that we finish the report by Tuesday.

4. Para 3 4 Recipients or intended person(s) Comparison (with a norm)
El regalo es para mi hermano.
The gift is for my brother.
¿Este es el discurso para el gobernador?
Is this the speech for the governor? 4
Comparison (with a norm)
Ella es muy alta para su edad.
She is very tall for her age.
Para un periódico liberal, presenta muchas opiniones tradicionales.
For a liberal newspaper, it presents many traditional opinions.

5. Para 5 Purpose or goal (to, in order to)
Pablo estudia para (ser) médico.
Pablo is studying to be a doctor.
Trabajo para ganar dinero para costear mi educación.
I work in order to earn money to pay for my education.

6. Para is used in some set phrases such as the following:
para siempre
forever
¿para qué?
what for?
para eso
for that (sarcastically)
no ser para tanto
not to be a big deal
sin qué ni para qué
without rhyme or reason

7. Por
Por is less direct and can point in various directions, including backward towards cause or motive.
Por indicates: 1
Duration of time (during, for) 2
Imprecise or approximate direction or time
around a certain time; through or by way of a certain location 3
Motive or cause 4
Exchange or interchange 5
Means or mode

8. Por 1 2 3 Duration of time Imprecise or approximate direction or time
Vamos a estar en Cancún por dos semanas.
We’re going to be in Cancún for two weeks.
Imprecise or approximate direction or time 2
Vamos a pasear por el parque por la tarde.
We’re going to take a walk through the park during the afternoon. 3
Motive or cause
Estudio español por amor al idioma.
I study Spanish because of a love for the language.

9. Por 4 5 Exchange or interchange Means or mode
Si no puedes ir a la reunión, yo voy por ti.
If you can’t go to the meeting, I’ll go in your place.
Pagué diez dólares por el CD de Óscar de León.
I paid ten dollars for the Óscar de León CD. 5
Means or mode
Siempre mando mis cartas por avión.
I always send my letters by air mail.
Vamos a viajar por tren.
We’re going to travel by train.

10. Por
Some other uses 1
Estar por + infinitive expresses readiness (to be about to do something)
Estoy por salir.
I am about to leave.
Estamos por visitar la tumba de Bolívar en el centro de Caracas.
We are about to visit Bolívar’s tomb in downtown Caracas. 2
“Per”
La velocidad máxima es de 70 millas por hora.
The speed limit is 70 miles per hour.

11. Por
Some other uses 3
Ir por, venir por = to go for, to come for or in search of something or someone
El conductor está gravemente herido. Voy por el médico.
The driver is gravely injured. I’ll go for the doctor. 4
Que queda por hacer = that remains to be done
Tengo dos proyectos por terminar.
I have two projects yet to be finished.
Eso está por verse.
That remains to be seen.

12. Por por ahora for now por aquí around here, this way por casualidad
Por is also used in a large number of set phrases such as the following:
por ahora
for now
por aquí
around here, this way
por casualidad
by chance
por completo
completely
por Dios
for God’s (goodness’ ) sake
por desgracia
unfortunately
por ejemplo
for example

13. Por por el bien de alguien for someone’s good por eso
Por is also used in a large number of set phrases such as the following:
por el bien de alguien
for someone’s good
por eso
therefore, for that reason
por favor
please
por fin
at last, finally
por lo general
in general
por lo menos
at least

14. Por por más que . . . no matter how much . . . por medio de
Por is also used in a large number of set phrases such as the following:
por más que . . .
no matter how much . . .
por medio de
by means of
por nada
you’re welcome
por si acaso
just in case
por suerte
luckily, fortunately
por supuesto
of course, naturally
por último
finally

15. FIN