Questions & Answers about П’ятий урок — завтра.
In Ukrainian, a dash is often used where English would use is.
So П’ятий урок — завтра literally looks like:
Fifth lesson/class — tomorrow
But it means:
The fifth lesson is tomorrow.
Ukrainian often leaves out the present-tense verb to be (є) in simple statements like this, especially in neutral written style. The dash helps show the link between the two parts of the sentence.
Because in Ukrainian, the present tense of to be is usually omitted.
So instead of saying something like П’ятий урок є завтра, Ukrainian normally just says:
П’ятий урок — завтра
This is very natural. English requires is, but Ukrainian usually does not in this kind of sentence.