i have played violin for like 9 months already and i still don't understand whether the notes are sharp or flat. say if theres one sharp does it mean 3 notes are sharp? i don't get it..

i don't understand your problem... but i'd like to help you.
if you try to re-explain maybe i'll get it.
do you not know what a key signature is?

If there's one sharp sign in the key signature (on the top line of the staff where an F would be), then all the F's are sharp, however many F's there are in the piece. If there are two sharp signs in the key signature (one on the top line of the staff where an F would be and one on the space where a C would be), then all the F's and C's are sharp--and so on.

'If there's one sharp sign in the key signature (on the top line of the staff where an F would be), then all the F's are sharp, however many F's there are in the piece. If there are two sharp signs in the key signature (one on the top line of the staff where an F would be and one on the space where a C would be), then all the F's and C's are sharp--and so on.'

Unless, of course, there's a sharp/flat/natural before a note anywhere in the music - then, I think (correct me if I'm wrong), that all following notes of that particular note change until the end of the bar or stated otherwise... or is it to the end of the stave... I think someone else is going to have to clear me up :p

Yes. These are called accidentals, and they temporarily override the key signature--until the end of the measure (also called the bar).

The original singular form--and in the view of many the only proper singular form--of staves in the musical sense, by the way, is staff, not stave. Stave is a back-formation from staves, the plural of staff. (Think of knife and knives, leaf and leaves, and so on.)

Ooh sorry, I've done very little theory so far - thank you for clearing that

oh ok i think i understand now. thanks everyone