Я напомню тебе о билете утром.

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Breakdown of Я напомню тебе о билете утром.

• билет: the ticket
• о: about
• утром: in the morning

Questions & Answers about Я напомню тебе о билете утром.

What tense/aspect is напомню, and why does it mean the future?

Напо́мню is the perfective form of напо́мнить in the so‑called “present” tense, but all present forms of perfective verbs refer to the future. So Я напо́мню = “I will remind (once, as a complete act).” If you want an ongoing or repeated future, use the imperfective: Я бу́ду напомина́ть (тебе о биле́те) “I’ll be reminding you / I’ll remind you repeatedly.”

Why is it тебе and not тебя?

Because напомнить governs the dative for the person: напомнить кому? → тебе (dative of ты). Тебя is accusative/genitive and would be wrong here. Formal/polite: вам. So: Я напо́мню тебе́… / Я напо́мню ва́м…

What case is о биле́те, and why that ending?

After о (“about, concerning”), Russian uses the prepositional case: о чём? → о биле́те (from nominative биле́т). Plural would be о биле́тах. The preposition literally marks the topic you’re reminding someone about.

Can I use про instead of о?