Which one do i need? Por? Para? or Nothing?
When do you know to use para? and when do you know to use por? If i want to write i went to the library every monday to read. How would that be translated? This sentence needs to be in the Imperfect form.
6 Answers
There are several articles, and I think two videos on por and para here on the site. Use those, and the online translator here to come up with something, and then any number of people here will be glad to suggest improvements, if need be.
thanks roger
You might find this lesson helpful - Por vs Para

You could start with this although I am sure there are other ways to say the same thing. In this case you can use para when using the english idea "in order to" do something.
Todos los lunes yo iba a la biblioteca para leer.
There are many lessons but like English you will get it over time and have that moment when you realise what sounds right and wrong by doing lots of listening!
I liked Paralee´s lesson #3.6 on this site. It covers the por vs. para distinction pretty thoroughly.
Well, I know that if you want to say "I went to the library every monday to read", you would probably want to say "Yo iba a la biblioteca cada lunes para leer".
Ir is in the Imperfect tense, and you use "para" to say "in order to".
As for "por", I do not know when you would use that.