V/V means the V chord of the V of the tonicSo if it were in G, V of G is D, and V of D is A. So, V/V in G is A
OK. But what is wrong with an A minor chord in an harmonic progression in the key of G? Actually it could make a nice change ie., II, V or V7, I.
Not to step over you vandermozart, but it's not labeled a II because of how the chord is functioning. In fact, a II chord (as far as I'm aware in Classical notation) does not exist, it will always be some form of secondary dominant.
-What are tips to correctly analyze phrasing? How can I be sure that what I think is a phrase really is a phrase?
Not to step over you, bachbrahmsschubert, but you're wrong; II is a very common chord in classical music. In fact, II6 is the most common pre-dominant chord of the classical era (much more common than IV). The reason V/V isn't labeled II is because these are two DIFFERENT chords. In the key of C major, V/V is D-F#-A, and II is D-F natural-A).
Isn't D-F natural - A written as "ii"? Because it's minor so you use lower case roman numerals.
-Does a repeat sign affect the number of measures? (Ex: A song has 8 measures but a repeat sign at the end - does that mean it really has 16 measures?)
I think you look for where the cadences are, that's the end of the phrase.