Держи меня в курсе.

Держи is the informal singular imperative of держать (to hold / keep).

In this expression, Russian uses the same idea English does in keep me informed:

• держать = to keep
• меня = me
• в курсе = in the know / informed / up to date

So Держи меня в курсе literally feels like Keep me in the know.

Because меня is the accusative case of я.

Here, держи takes a direct object: keep whom? → me.
So:

• я = I
• меня = me (accusative/genitive form)
• мне = to me / for me (dative)

In this sentence, Russian needs the equivalent of English me, so меня is correct.

В курсе is a very common idiomatic expression meaning:

• informed
• up to date
• aware of what’s going on
• in the loop

You will often see it in the phrase быть в курсе = to be informed / to know what’s going on.

Examples:

• Я не в курсе. = I’m not aware / I don’t know about it.
• Ты в курсе? = Are you aware? / Do you know?

So in Держи меня в курсе, the idea is keep me in that informed state.

Because the expression is fixed as быть / держать кого-то в курсе.

The preposition в often takes the prepositional case when it means in a location or state.
Here, курсе is the prepositional singular form of курс.

So grammatically:

• в
  • prepositional
• курс → в курсе

Even though the whole phrase is idiomatic, it still follows a normal case pattern.

It is informal singular — used when speaking to:

• one friend
• one colleague you address with ты
• one family member
• one person in a casual setting

The formal or plural version is:

Держите меня в курсе.

Use Держите меня в курсе when speaking to:

• one person you address with вы
• several people

Yes, very natural. It is a standard everyday phrase.

Native speakers use it in situations like:

• work updates
• travel plans
• family news
• ongoing problems
• project progress

It sounds normal in both spoken and written Russian.

Examples:

• Если что-то изменится, держи меня в курсе.
• Держите меня в курсе событий.

By itself, Держи меня в курсе is an imperative, so grammatically it is a command. But in real use, it is often not harsh. Depending on tone, it can sound like:

• a friendly request
• a practical instruction
• a casual reminder

If you want to make it softer, Russian often adds words like:

• пожалуйста = please
• если что = if anything comes up
• ладно? = okay?

For example:

• Держи меня в курсе, пожалуйста.
• Если будут новости, держи меня в курсе.

So the phrase itself is neutral; tone and context matter.

A helpful approximation is:

dyr-ZHEE mi-NYA f KOOR-sye

More accurately:

• держи — stress on the second syllable: держИ
• меня — stress on the second syllable: менЯ
• курсе — stress on the first syllable: кУрсе

One useful pronunciation detail:
the в in в курсе is often pronounced more like f, because it comes before the voiceless к.

So it may sound like:

• меня ф курсе

That is normal Russian pronunciation.

Russian uses the imperfective verb держать here because the idea is maintain an ongoing state: keep me informed over time.

You are not asking for one single completed action, but for continuous updates.

That is why держи / держите sounds natural.

A perfective verb would not fit this expression well, because the point is not inform me once and finish, but continue keeping me updated.

The formal/plural version is:

Держите меня в курсе.

It comes from the same verb держать:

• держи = imperative for ты
• держите = imperative for вы or plural you

So:

• Держи меня в курсе. = informal, one person
• Держите меня в курсе. = formal one person or multiple people

Yes, very naturally.

Common expansions include:

• Держи меня в курсе событий. = Keep me updated about what’s happening.
• Держи меня в курсе ситуации. = Keep me updated about the situation.
• Держите меня в курсе новостей. = Keep me updated on the news.

You can also build longer sentences:

• Если что-нибудь узнаешь, держи меня в курсе.
• Пожалуйста, держите меня в курсе всех изменений.

Yes. Some common alternatives are:

• Дай мне знать. = Let me know.
  Usually more like telling someone to inform you when something happens.

• Сообщи мне. = Inform me / tell me.
  More direct and often more neutral.

• Информируй меня. = Keep me informed / inform me.
  Understandable, but more formal or bookish in many contexts.

• Не забудь сообщить мне. = Don’t forget to tell me.

Compared with these, Держи меня в курсе specifically suggests ongoing updates, not just one message.

Yes. It works well whenever something may develop over time.

Common contexts:

• work projects
• medical updates
• travel delays
• family matters
• negotiations
• technical issues

For example:

• Как только будут результаты, держи меня в курсе.
• Если он ответит, дай знать — и вообще держи меня в курсе.

So it is especially useful when you expect new information to appear later.