Grammar Help?

[LunaW0lf]

Quick Information:
I am 15 years old. My first language is Spanish not English, so if my grammar sucks, you know why. Another reason my grammar may suck is because I never received a grammar lesson before September of '05. So feel free to correct my grammar.
Anyway....
I like different languages and learn as many as I can. I started an online Latin class last Monday, and the teacher is no help at all. I e-mailed her about some trouble I was having with an assignment where she keeps asking about the word endings. The endings change according to how the words are being used, but sometimes I can't really figure out how they are being used. These are the things that confuse me and if you could give a couple of examples, I'd love it.

Predicate Nominative
Direct/Indirect objects
Prepositions

I need an explanation of what those are (in the simplest way put, please) and an example if possible. I sort of understand what they are, but still have trouble picking out which ones are which in a sentence.

If you can help, that would be great. ^_^

Hopefully I posted this in the right place.....sorry if I didn't  

[Ame Yuki Kaze]

Predicate nomative
Direct/indirect objects
Prepositions  

[Dead Twisted Romance]

Yami no Hitokiri

Predicate nomative
Direct/indirect objects
Prepositions

Well put smile  

[Ind1v1dual]

Nice to meet you :]