Question

Which of these sentences should use por instead of para ?
Voy a caminar para Las called.
Voy a la Casas para dormer.
Voy a or para El cine.
Para mi, UN café

Answer 1

Basically, "por" is used to express movement through time or space. This can be:

- A physical transition such as traveling

Viajé por Francia y España. (I traveled through France and Spain.)
- An exchange of objects

Pagaré $3 por este sandwich. (I will pay $3 in exchange for this sandwich.)
- A duration of time

Tengo que trabajar por ocho horas hoy. (I need to work for eight hours today.)
- A motivation/reason for doing something

Por su amor a los niños, quiere ser pediatra. (Because of her love for children, she wants to be a pediatrician.)

Answer 2

And "para" is generally used to convey destinations or end points. These can be:

- Physical locations
Salgo para Chile mañana. (I leave for Chile tomorrow.)

- People (recipients)
Este regalo es para Adela. (This gift is for Adela.)

- Deadlines
Necesito la presentation para el viernes. (I need the presentation by/on Friday.)

- Goals
Trabaja mucho para ganar más dinero. (He works a lot in order to earn more money.)

Answer 3

I'd go with the first one though I don't understand the answers that much. They aren't well written

Answer 4

It's "dormir" not "dormer". "Calles" not "called".

Voy al cine --> never por or para. "a" is the movement preposition, for instance, when you go somewhere. A+el = al.
"Para el cine" would be a goal.

*Para* mi--> for me, always para. It's a kind of goal.

Voy a la casa *para* dormir ---> goal

Voy a caminar *por* las calles. ---> through the streets, by the streets.

Can you see the difference now?

Para: goal/destination/person.

Por: through, by. Geographical mean.