I'm so glad to hear that its turning out well for you.

The English laguage is a terribly frustrating thing for people to learn as a second language, because words can have so many different meanings. ('just an aside).

Your strings are 'flat' in the sense that they sound 'dull' another word with many meanings. New strings have a rich, full, sound that you will instantly recognize as an improvement. 'Sustain', which is how long a plucked string will continue to vibrate, should also be improved.