A:
This is a huge topic !!!! And I partially answered in your other message but here are a few more thoughts for you:
1) mostly TO = A and FOR = POR/PARA. A big issue is that PARA followed by an infinitive is also (often) translated as "TO", but that is because of the infinitive. For example:
"Lo hice para ayudar a HDGD" = I did it to help HDGD. "to" is part of "TO HELP" the same as "voy a ayudarlo" = "I am going to help him". "I did it for to help HDGD" sounds awful.
2a) mostly FROM/OF = DE. A big issue is when you see DE, knowing which one to translate to. I would say as a very general rule:
- FROM is about locations (I am from Mexico, I came from work today etc.)
- OF is about characteristics and possession (The capital of Mexico is Mexico City, this is not a location, it's something Mexico "possesses", the subject of the book is X)
2b) Another big issue is that Spanish uses DE way more than English does, for at least two reasons:
a) possessives - la capital de México = Mexico's capital
b) noun phrases - la portada del libro = the book cover
3) I don't see the issue with with-to, with = con, to = A. Lots of problems with To/A, but WITH seems like a pretty direct translation, notwithstanding a few verbs in Spanish use it in ways that are really weird to us. These are very verb-specific.
- casar con = get married to
- soñar con = dream about
- ten cuidado con = be careful OF
That's all I have for now ;)