Questions & Answers about Сьомий урок сьогодні.
Because Ukrainian often leaves out the present-tense form of to be.
So Сьомий урок сьогодні. is a normal complete sentence even though there is no spoken є.
Literally, you can think of it as something like:
Сьомий урок [є] сьогодні.
This is very common in Ukrainian. In the present tense, the verb to be is usually omitted unless you are making a special emphasis or using a different structure.
Сьомий is an ordinal number, meaning seventh.
In Ukrainian, ordinal numbers behave like adjectives, so they change to match the noun in:
- gender
- number
- case
Here it is masculine singular nominative because it matches урок, which is also masculine singular nominative.
So:
- сьомий урок = seventh lesson / seventh class period
Compare:
- сьома година = seventh hour
- сьоме питання = seventh question
- сьомі уроки = seventh lessons