Learn Hardcore Russian: На завтрак я делаю бутерброд с колбасой и сыром. - For breakfast I make a sandwich with sausage and cheese.

На завтрак literally means “for breakfast.” In Russian, на + accusative is a common way to say “for (a meal or occasion).” You’re indicating purpose or timing (“what you eat for breakfast”).

What case is завтрак in, and why doesn’t it change its ending?

Here завтрак is in the accusative singular because it’s the object of the preposition на. Since завтрак is a masculine inanimate noun, its accusative form is identical to its nominative form—no ending change.

Why is бутерброд also in the accusative case, and why doesn’t it end in -а?

Бутерброд is the direct object of the verb делаю (“I make”), so it must be in the accusative. It’s masculine and inanimate, so accusative = nominative (no -а ending). If it were animate (e.g. я вижу брата), it’d take a different form.

Why do we use the verb делаю here? Could we say готовлю or делаю завтрак?

Дела́ть
- object often means “make” in a general sense (e.g. make a sandwich).
Готови́ть means “to cook/prepare,” which also works: На завтрак я готовлю бутерброд… but it’s more neutral and focuses on cooking rather than assembling.
Делаю завтрак would imply “I make breakfast (the whole meal),” whereas делаю бутерброд specifies just the sandwich.

What case are колбасой and сыром, and why do they look that way after с?

The preposition с (“with”) requires the instrumental case.

колбаса → колбасой (instr. sing.)
сыр → сыром (instr. sing.)
Together с колбасой и сыром means “with sausage and cheese.”

Could we say бутерброд из колбасы и сыра instead of с колбасой и сыром? What’s the difference?

из
- genitive describes material or origin (“made of”): бутерброд из колбасы would weirdly suggest a sandwich made entirely of sausage.
с
- instrumental describes accompaniment or addition (“with”): бутерброд с колбасой и сыром is the normal way to say “a sandwich that has sausage and cheese.”

Is the pronoun я necessary here, or can it be omitted?

Russian often drops the subject pronoun because the verb ending already shows the person. You can say:

На завтрак делаю бутерброд…
and it’s perfectly fine in casual speech. Including я adds emphasis or clarity.

How flexible is the word order? Could I say Я на завтрак делаю бутерброд с колбасой и сыром?

Word order in Russian is relatively free, since cases show each word’s role. Changing the order only shifts the emphasis:

На завтрак я делаю… (focus on time/purpose)
Я на завтрак делаю… (focus on who is doing it)
Я делаю на завтрак… (neutral statement)
All are grammatically correct.