Questions & Answers about Cieszę się, że jutro mamy wolne popołudnie.
Because cieszyć się is a fixed reflexive verb in Polish meaning to be happy / to be glad / to rejoice.
- cieszę by itself would come from cieszyć, which usually means to please or to make someone happy in a different structure.
- cieszę się means I’m glad or I’m happy.
So in this sentence:
- Cieszę się = I’m glad
The się does not translate neatly into English here, but it is required.
Że means that.
It introduces the second clause:
- Cieszę się, że... = I’m glad that...
In English, that is often optional:
- I’m glad that we have a free afternoon tomorrow
- I’m glad we have a free afternoon tomorrow
In Polish, że is very commonly used in this kind of sentence.