Questions & Answers about Wydaje mi się, że on śpi.
Why is there both mi and się after wydaje?
The verb wydawać się is a reflexive verb that means 'to seem.' So, wydaje się means 'it seems.' To state who it seems to, you use the dative case. Mi is the short dative form of ja (I). Put together, wydaje mi się translates literally as 'it seems itself to me.'
Could I change the order and say Wydaje się mi?
It is much better to stick to Wydaje mi się. Short pronouns like mi and się tend to cluster together in Polish, but się generally comes last in a group of short pronouns. Putting mi before się is the standard, most natural-sounding order.
What is the dictionary form of śpi, and why does it look so different?
The dictionary form (infinitive) is spać (to sleep). It is an irregular verb. In the present tense, the base changes from sp- to śp- for most forms, which is why we get ja śpię (I sleep), ty śpisz (you sleep), and on śpi (he sleeps).
Do I have to include on here, or could I just say ...że śpi?