Hi sintink, and welcome, No problem with your English. But please do use capital letters to start sentences, and refrain from using SMS language like 'u' for 'you' and '2' for 'too'. What you are asking about is 'tone production' (not 'tonality', that is the harmonic language of the music itself). The word 'tuts' must be the Indonesian variant of the Dutch word 'toets', which in English is 'key'. Many people can endlessly discuss the various ways to press/hit/strike a key. But I strongly believe that very few people can actually, at equal volume, hear the difference. A teacher should probably not bother a pupil with this kind of ultra-subtle detail. Just tell her that you do not hear the difference, and then she should leave it alone. Sound is important, but it is the music that comes first.