what does this mean, translate these two sentences to english: kiyouha doyoubi desu, ga gatsukouni ikimasen and kiyouha doyoubi desu, kara gatsukouni ikimasen.

The sentences you provided are already in Japanese. Here are their translations into English:

1) "Today is Sunday, but I won't go to school."
2) "Today is Sunday, so I won't go to school."