Mandarin 101

This happened many years ago when i was still in Secondary school. I was walking down the road to go to leisure mall when this old lady walked up to me(everyone else there could speak better mandarin than i do but she choose to talk to me) and started speaking to me in mandarin, i didn't understand a thing she was saying so i politely said "WO PU YAO CHIANG HWA YEE".

Next thing i knew she was like cursing and shouting at me. ????? and walked away...

Then i asked my friend what i said?

Its suppose to be said "WO BU HUI CHIANG HWA YEE" not the other one... hehehehe

WO PU YAO CHIANG HWA YEE - i don't want to speak mandarin
WO BU HUI CHIANG HWA YEE - i don't know how to speak mandarin