Native Dutch speaker here. "Voorbereiden" means something like to prepare in advance, used in sentences like "I will prepare my house for when the guests will come". "Bereiden" means something like making food/dinner, used in sentences like "I'm going to prepare some food for later". Hope this helps :) If you have any other questions or just want to talk just message me ^^

And some prefixes are easier of course. Things like voor- (before, in place or time), bij- (with), na- (after), op (up, on top), uit (out). So if you take the verb ''slaan'' (to hit) you can make a lot of combination. Slaan = hit, ontslaan = to fire someone, beslaan = become foggy (like what windows do when it's cold and humid), verslaan = to win from someone/to beat someone, opslaan = to store/to beat (the first ball you hit when playing tennis, volleyball, ''you beat it upwards'' = opslaan), uitslaan = exclaim (to beat ''out'') (ex: wartaal uitslaan = to exclaim gibberish language).

I understand your troubles. I think that understand the prefixes will already help you a long way to understand the meaning of either words. Here's a list of some dutch prefixes you'll see. Negating: on-, niet-, non-. Ex: Recht --> onrecht. (justice - injustice) Repetition: her-. Ex: herhalen. Indicating the object of an action:(I believe): be-. Ex: werken --> bewerken (work - edit) Oefenen --> beoefenen (http://www.italki.com/question/239306). Indicating change: ver-. Ex: vervellen (van vel veranderen / losing/changing skin). Negative connotation: wan-. Orde --> wanorde (order, disarray). Another important prefix: -ont http://nl.wiktionary.org/wiki/ont- I hope that all this is helpful for you And some more.. Sorry if this all appears a bit chaotic ! :D