Knowing when to use para or por
Knowing whether to use por or para can be very confusing for English speakers. They can both be used to mean for (as well as other things) so choosing which to use is not straightforward:
Trabajo por mis hijos.
I work for my children (i.e. for their benefit)
Trabajo para mis hijos.
I work for my children (i.e. they employ me)
As you can see, just one small word can make a big difference to the meaning of a sentence, therefore it is important that you learn how to use these prepositions so that you can improve your accuracy.