Breakdown of Завтра я решу задачу номер восемнадцать или девятнадцать.
я
I
завтра
tomorrow
решить
to solve
задача
task
Questions & Answers about Завтра я решу задачу номер восемнадцать или девятнадцать.
Why don't восемнадцать and девятнадцать change their endings to match the accusative case of задачу?
In this sentence, the numbers are used as a label or ID (problem number 18), not to count a quantity of problems (like "18 problems"). When used as a name or label like this, the number stays in its dictionary form (the nominative case).
Where does the word ending -надцать come from in these numbers?
It comes from old Russian meaning "on ten". So восемнадцать literally means "eight on ten". Notice that the soft sign (ь) that usually appears at the end of восемь (8) and девять (9) is dropped in the middle of these combined words, leaving only the soft sign at the very end.
Why does решу mean "will solve" without using the future tense word буду?
Решить is a perfective verb, meaning it focuses on a completed result. In Russian, when you apply standard present-tense endings to a perfective verb (like я решу), it automatically expresses the future tense. You only use буду (I will) with imperfective verbs.
Why is the word for problem spelled задачу here instead of its dictionary form задача?