POR
by, by means of :
Hablo por teléfono con mis amigos.
(I talk on the phone with my friends)
through, along :
Paseamos por el parque.
(We walk through the park.)
during, in (time of day) :
Pedro trabaja por la tarde todos los días.
(Pedro works in the afternoon every day.)
because of, due to :
Victor está preocupado por el examen.
Victor is worried about (because of) the test.
for = in exchange for
Le di diez dólares por el boleto.
(I gave him ten dollars for the ticket.)
for = for the sake of, on behalf of
Mi abuelo trabajaba mucho por la familia.
(My grandfather worked a lot for the sake of the family.)
for = duration (often omitted)
Fuimos de vacaciones (por) dos semanas.
(We went on vacation for two weeks.)
PARA
in order to + infinitive
Estudio mucho para sacar buenas notas.
I study hard (in order) to get good grades.
for = destined for, to be given to
El regalo es para mi mamá.
(The gift is for my mom.)
for = by (deadline, specified future time)
Tengo que escribir una composición para el viernes.
(I have to write a composition for Friday.)
for = toward, in the direction of
Salimos mañana para Puerto Rico.
(We leave for Puerto Rico tomorrow.)
for = to be used for
Este cuaderno es para la clase de español.
(This notebook is for Spanish class.)
for = as compared with others, in relation to others
Para ellos, las matemáticas son fáciles.
(For them, math is easy.)
for = in the employ of
Mi padre trabaja para una compañía de seguros.
(My father works for an insurance company.)