"Wiemy co tam robiłeś!"

Translation: We know what you have been doing there!

[pdforbes86]

listening to this slow, it still sounds like wiem and not wiemy

[BrianH71]

I think that's the nature of learning a new language. I constantly have that problem of not recognizing words as they are spoken, even when I know all the words. Keep practicing... :-) But, yes, the text-to-speech can also be poor or even a bit wrong at times.

[Mostlaszlo]

Prove it :P