Я завернул подарок в бумагу.

Завернул is the past tense, masculine singular form of the verb завернуть.

A few important things are packed into this one word:

• за-вер-ну-л
• завернуть is the perfective verb
• завернул means wrapped / finished wrapping

So the sentence presents the action as completed:
I wrapped the gift in paper.

If you wanted the imperfective version, you would usually use заворачивать:

• Я заворачивал подарок в бумагу. = I was wrapping / I used to wrap the gift in paper.

Also, the ending -л here shows the speaker is masculine. A female speaker would say:

• Я завернула подарок в бумагу.

In Russian, the past tense agrees in gender and number.

So:

• завернул = masculine
• завернула = feminine
• завернуло = neuter
• завернули = plural

That means:

• Я завернул подарок в бумагу. = said by a man
• Я завернула подарок в бумагу. = said by a woman

This is very different from English, where I wrapped does not show gender.

Подарок is the direct object of the verb, so it goes in the accusative case.

The verb answers the question:

• завернул что? = wrapped what?
• подарок = the gift

For an inanimate masculine noun, the accusative singular is often the same as the nominative singular. So:

• nominative: подарок
• accusative: подарок

That is why the form does not visibly change here.

Here в is used with the accusative: в бумагу.

That is because the phrase expresses the idea of putting/enclosing something into something as the result of the action:

• завернуть во что? = to wrap something in / into what?
• в бумагу

So в бумагу means something like:

• into paper
• so that it ends up wrapped in paper

By contrast, в бумаге would be prepositional, which usually suggests location:

• в бумаге = in the paper / inside the paper as a location or state

That is not the normal form after завернуть in this meaning.

This is just a normal Russian pattern with this verb.

Russian often thinks of the action as moving something into an enclosing layer:

• завернуть подарок в бумагу
• literally something like wrap the gift into paper

In natural English, we say:

• wrap the gift in paper

So even though the English translation uses in, the Russian grammar is based on the pattern:

• завернуть что во что

This is something worth memorizing as a verb pattern.

Yes. Russian can express a similar idea with a different verb and a different case pattern.

For example:

• Я обернул подарок бумагой.

Here:

• обернул = wrapped around
• бумагой = instrumental case

So Russian has more than one way to express wrapped the gift in paper.

But in your sentence, the chosen pattern is:

• завернуть что в бумагу

That is completely natural.

Yes, very often.

You can say:

• Завернул подарок в бумагу.

Russian often drops subject pronouns when the subject is clear from context.

However, there is one small difference from present tense verbs: in the past tense, the verb shows gender and number, but not person. So завернул tells us:

• singular
• masculine

but not automatically I versus he.

Because of that, Я may be kept if the speaker wants to make it explicit.

Я завернул подарок в бумагу. has a very normal, neutral word order:

• Я = subject
• завернул = verb
• подарок = direct object
• в бумагу = prepositional phrase

This is a straightforward, unmarked way to say it.

Russian word order is flexible, so other versions are possible, for example:

• Подарок я завернул в бумагу.
• В бумагу я завернул подарок.

These can shift emphasis or focus, but your original sentence is the most neutral/basic version.

The dictionary form is завернуть.

When you look up verbs in Russian dictionaries, you normally look for the infinitive form, not the past form.

So:

• завернул → look up завернуть

Its imperfective partner is usually:

• заворачивать

So a learner may want to remember the pair:

• завернуть = perfective
• заворачивать = imperfective

The main difference is aspect.

• завернуть = perfective

  • one completed action
  • result matters

• заворачивать = imperfective

  • process, repetition, habit, or background action

Examples:

• Я завернул подарок в бумагу.
  = I wrapped the gift in paper.
  The wrapping is finished.

• Я заворачивал подарок в бумагу, когда ты позвонил.
  = I was wrapping the gift in paper when you called.

• Я всегда заворачиваю подарки в красивую бумагу.
  = I always wrap gifts in nice paper.

Because бумага is a feminine noun, and here it is in the accusative singular after в.

So:

• nominative: бумага
• accusative: бумагу

This is a very common pattern for feminine nouns ending in -а:

• книга → книгу
• машина → машину
• бумага → бумагу

Not necessarily. Бумага just means paper in a general sense.

So this sentence means the gift was wrapped in paper, and the exact kind of paper is not specified.

If needed, Russian could be more specific:

• в подарочную бумагу = in wrapping paper / gift paper

But в бумагу is perfectly understandable and natural if the context already makes it clear.

It would be:

• Я завернула подарок в бумагу.

Only the past tense verb changes:

• masculine: завернул
• feminine: завернула

The rest of the sentence stays the same.

It is about the finished result.

Because завернуть is perfective, the sentence presents the action as completed:

• the gift is now wrapped

If you wanted to focus on the process instead, you would normally use the imperfective verb:

• Я заворачивал подарок в бумагу. = I was wrapping the gift in paper.

So the original sentence is best understood as:

• I wrapped the gift in paper
• not I was wrapping the gift in paper