Он представляет нашу компанию.

Yes, Russian often drops subject pronouns when the subject is clear from context, so Представляет нашу компанию can be possible in conversation.

But он is included here because it:

• makes the subject explicit,
• adds a little emphasis or contrast,
• is natural when this is a standalone sentence for learning.

So both are possible, but Он представляет нашу компанию is the clearer full sentence.

Here представляет means represents.

The verb представлять is a very common Russian verb with several related meanings, including:

• to represent
• to present
• to introduce
• sometimes to imagine in expressions like представлять себе

So this is a verb where context matters a lot. In Он представляет нашу компанию, the meaning is clearly He represents our company.

Представляет is:

• 3rd person singular
• present tense
• imperfective

It matches он (he), so the ending is -ет:

• я представляю = I represent
• ты представляешь = you represent
• он/она представляет = he/she represents

Because Russian present-tense forms agree with the subject, он requires представляет.

In Russian, an actual present-tense meaning normally uses the imperfective verb.

So:

• представлять = imperfective
• представить = perfective

That means:

• Он представляет нашу компанию = He represents our company / He is representing our company

The perfective partner представить does not normally mean a regular present action. Its future form would mean something like will present / will introduce / will submit, depending on context.

Because they are the direct object of the verb.

The verb представлять here takes an object in the accusative case: he represents what? — our company.

So:

• наша компания = our company (nominative, dictionary-like form)
• нашу компанию = our company (accusative)

Both words change because the noun is feminine singular, and the adjective must agree with the noun.

Наша is the feminine singular nominative form of our.

Since компания is a feminine noun and here it is in the accusative, the adjective also changes to accusative:

• наша компания = our company
• я вижу нашу компанию = I see our company
• он представляет нашу компанию = he represents our company

So нашу is simply the feminine singular accusative form of наш.

Because компания is a feminine noun ending in -я, and in the singular accusative that ending becomes -ю.

So:

• компания = nominative
• компанию = accusative

This is a very common pattern for feminine nouns ending in -а or -я.

For example:

• машина → машину
• неделя → неделю
• компания → компанию

Yes. Russian word order is more flexible than English because case endings show who is doing what.

The neutral order here is:

• Он представляет нашу компанию.

But you could also hear:

• Нашу компанию он представляет.
• Представляет он нашу компанию.

These variants change the emphasis, not the basic meaning. For learners, the standard neutral order Он представляет нашу компанию is the best one to use first.

Usually, in this exact sentence, the most natural meaning is He represents our company.

Because представлять can also mean to introduce or to present, context matters. For example:

• Он представляет нового сотрудника. = He is introducing a new employee.
• Он представляет проект. = He is presenting the project.

With компанию, both represents and sometimes presents are theoretically possible, but without extra context, learners should understand this sentence as He represents our company.

A useful stress guide is:

• Он
• представлЯет
• нАшу
• компАнию

So the stressed syllables are:

• представляет
• нашу
• компанию

A rough pronunciation guide for English speakers:

• on preet-stav-LYA-yet NA-shoo kom-PA-nee-yu

Not exact English pronunciation, but close enough to help.

Not always. Компания can mean:

• a company or business,
• a group of people / crowd / social company, depending on context.

In нашу компанию, because of the verb представляет, the business meaning our company is the natural one.

So this sentence is understood as talking about an organization, not just a group of friends.

Normally, no. The natural Russian verb here is представлять.

Even though English uses represent, Russian does not usually use a direct borrowed equivalent in everyday speech for this meaning. So:

• natural: Он представляет нашу компанию
• unnatural or very nonstandard for most learners: Он репрезентует нашу компанию

This is a good example of why direct word-for-word translation from English can be misleading.