QUOTE(petrat @ Sep 16 2007, 06:23 AM)

You would add chords to form a cadence on the last two notes in the scale in this case. In C major you would use the chord of G as you play D and the chord C to harmonise the final C of the scale. That would give you the chord progression of V to I, forming a perfect cadence. Remember that you do not play cadences in scales for AS piano exams though.
Thank you Petrat, I will ask my teacher to show me this. Yep, do know I don't play them in exam, thanks again