Questions & Answers about Kiedy on pracuje, ja śpię.
Normally Polish drops pronouns like ja and on. Why are they included here?
You are right that pronouns are usually dropped! Here, they are used to show a strong contrast between two different people. Using on and ja emphasizes that he is doing one thing while I am doing another.
The dictionary form of the verb for to work is pracować. Why does it change to pracuje?
Verbs ending in -ować have a special pattern. You drop the -ować and replace it with -uj- before adding the ending. Since the subject is he (on), we add the he/she/it ending -e, giving us pracuje.
The verb for to sleep is spać. Why does the spelling change so much to become śpię?
Spać is an irregular verb. When conjugated for I (ja), the hard s softens to ś, and the p becomes pi before we add the standard I ending, which is -ę.
Is the comma after pracuje required?
Yes! In Polish, you almost always use a comma to separate two parts of a sentence that each have their own subject and verb. Here, we must separate the clause about him working from the clause about me sleeping.