Сегодня утром я купила свежую булку и маленький пончик в новой булочной.

Because купила shows that the speaker is female.

In the past tense, Russian verbs agree with the subject in gender and number:

• я купил = I bought (said by a man)
• я купила = I bought (said by a woman)
• мы купили = we bought

So this sentence tells us that the person speaking is female.

Both words are direct objects, so they are in the accusative case. But they change differently because they belong to different noun types.

• булка is a feminine noun:

  • nominative: булка
  • accusative: булку

• пончик is a masculine inanimate noun:

  • nominative: пончик
  • accusative: пончик

For many masculine inanimate nouns, the accusative is the same as the nominative.
For many feminine nouns ending in -а, the accusative changes to -у.

That is why we get:

• купила свежую булку
• и маленький пончик

Because adjectives must agree with the nouns they describe in gender, number, and case.

Here:

• булку is feminine singular accusative
• пончик is masculine singular accusative and inanimate

So the adjectives must match:

• свежая булка → свежую булку
• маленький пончик → маленький пончик

Notice that masculine inanimate accusative often looks the same as the nominative, so маленький does not change here.

Because this phrase describes location, not movement toward a place.

Russian uses в with different cases depending on meaning:

• в + accusative = motion into somewhere
  
  • идти в булочную = to go to the bakery
• в + prepositional = being inside / at a place
  
  • в булочной = in / at the bakery

In your sentence, the buying happened at the bakery, so Russian uses the prepositional case:

• в новой булочной = in / at the new bakery

Because the adjective must match булочной, which is in the prepositional case.

Base form:

• новая булочная = a new bakery

After в for location, булочная becomes prepositional singular:

• в булочной

So the adjective changes too:

• новая → новой

That gives:

• в новой булочной

Yes. They are related.

• булка = a bun, bread roll, loaf-like baked item, depending on context
• булочная = a bakery / bread shop

Historically and structurally, булочная comes from the same root and originally means something like bread shop or bun shop.

A useful comparison:

• булка = the baked item
• булочная = the place where you buy it

Сегодня утром means this morning or literally today, in the morning.

The word утром is the instrumental form of утро, but in expressions of time it often works like an adverb:

• утром = in the morning
• вечером = in the evening
• днём = in the daytime / during the day
• ночью = at night

So Сегодня утром is a very natural Russian way to say this morning.

Russian has no articles, so there is no direct equivalent of a, an, or the.

So:

• свежую булку can mean a fresh roll or the fresh roll
• маленький пончик can mean a small doughnut or the small doughnut

Context tells you whether the meaning is definite or indefinite.

Yes, Russian word order is more flexible than English because case endings show grammatical roles.

The neutral order here is:

• Сегодня утром я купила свежую булку и маленький пончик в новой булочной.

But other orders are possible, for example:

• Я сегодня утром купила свежую булку и маленький пончик в новой булочной.
• В новой булочной я сегодня утром купила свежую булку и маленький пончик.

These versions still mean roughly the same thing, but the emphasis changes. Russian often moves words around to highlight time, place, or contrast.

Yes, very often.

Russian often omits subject pronouns when they are clear from the verb form or context. So you could say:

• Сегодня утром купила свежую булку и маленький пончик в новой булочной.

This is natural if it is already clear who is speaking.
However, я is still perfectly correct and may be used for clarity, emphasis, or contrast.

Because пончик is inanimate.

In Russian, masculine singular nouns in the accusative behave differently depending on whether they are animate or inanimate:

• inanimate: accusative = nominative
• animate: accusative = genitive

So:

• вижу пончик = I see a doughnut
• вижу брата = I see my brother

Since a doughnut is inanimate, the correct form is пончик, not пончика.

Not exactly.

Булка can be tricky because its meaning depends on context. It can refer to:

• a bun
• a bread roll
• sometimes a loaf or a type of white bread product

It is not always the same as general English bread.
For general bread as a substance, Russian often uses хлеб.

So roughly:

• хлеб = bread in general
• булка = a specific baked item such as a bun or loaf-type piece

Because в новой булочной is not another item in the shopping list. It tells us where the buying happened.

The structure is:

• я купила = I bought
• свежую булку и маленький пончик = the two things bought
• в новой булочной = where it happened

So the sentence means:

• This morning I bought a fresh roll and a small doughnut at the new bakery.

The final phrase is attached to the whole action, not coordinated as a third noun.

It is the prepositional singular form of булочная.

The dictionary form is:

• булочная

After в meaning location, it becomes:

• в булочной

And with the adjective:

• в новой булочной

So if you are parsing the sentence word by word:

• сегодня = time word
• утром = adverbial time expression
• я = subject
• купила = past-tense verb, feminine
• свежую булку = direct object, accusative
• и маленький пончик = second direct object, accusative
• в новой булочной = prepositional phrase showing location