"ab" and "nach"in this sentence

An der großen Kreuzung biegen Sie dann nach rechts ab.

In this sentence, what does the "ab"mean? I don't think it is meant to split off

Oh by the way, while we're at it, what is "nach"there for as well? I know "nach"can mean "turn" but I thought "biegen"was there for that?

There are times when I think I'm getting the hang of this German stuff but then I have days where I think "man am I confused"

hi Grant,
Go to stackexchange, then I would like to see the result.  

Thanks for that Errant and I have gone and signed up there. I was hoping that I would find an answer on this forum though

Hi Grant,

I believe the verb abbiegen means to bend, or to turn off (as in turn off a path/road). It's separable, so the ab goes at the end of the clause. Not sure what the difference between this and biegen is - it might be intransitive (i.e. the road bends = die Straße biegt ab) while biegen on its own is transitive. 

I'm guessing though, so would appreciate Paul's input!

For some more info, here's a link (to one of Rocket's competitors, sorry!)

https://www.duolingo.com/comment/1870535
 

Thanks for info and both posts Peter.  I checked out the commentary on duolingo. It explains it well. Good stuff