Not an expert, but I am guessing first pic':
Rana temporaria, the European Common Frog
or possibly
Rana dalmatina - Agile Frog
Rana arvalis - Moor Frog
(are the second two found in Poland?)
Second Pic':
Pelophylax lessonae - Pool frog
(but 'green' or 'water' frogs in Europe all seem to look very similar and can even interbreed, which complicates things)