Полицейский хочет прекратить разговор.

It is a noun here, meaning police officer / policeman.

Historically, полицейский is related to an adjective meaning police-related, but in modern Russian it is very commonly used as a noun for a police officer.

In this sentence, полицейский is in the nominative singular masculine form because it is the subject of the sentence.

You can think of it as:

• полицейский = a police officer
• полицейская = a female police officer
• полицейские = police officers

So even though its ending looks adjective-like, here it functions as a regular noun.

Хочет is the 3rd person singular form of the verb хотеть (to want).

The subject is полицейский = the police officer, which is he in English, so Russian uses the he/she/it form:

• я хочу = I want
• ты хочешь = you want
• он / она хочет = he / she wants
• мы хотим = we want
• вы хотите = you want
• они хотят = they want

So:

• Полицейский хочет... = The police officer wants...

Because after хочет (wants), Russian commonly uses an infinitive to express what someone wants to do.

So the structure is:

• [someone] хочет + infinitive
• [someone] wants to + verb

Examples:

• Он хочет уйти. = He wants to leave.
• Она хочет спать. = She wants to sleep.
• Полицейский хочет прекратить разговор. = The police officer wants to end the conversation.

So прекратить is simply the verb to stop / to put an end to in infinitive form.

This is about verb aspect, which is very important in Russian.

• прекращать = imperfective
• прекратить = perfective

In this sentence, прекратить is used because it refers to a single completed action: ending the conversation.

So:

• хочет прекращать would sound unusual here, because it suggests an ongoing/repeated process rather than the completed result.
• хочет прекратить разговор means he wants to bring the conversation to an end.

A simple way to think of it:

• imperfective = process / repetition / general action
• perfective = completed result / one whole action

Since ending a conversation is usually viewed as a complete event, прекратить is the natural choice.

It is in the accusative.

The verb прекратить takes a direct object, so разговор is in the accusative case. But for many inanimate masculine nouns, the accusative form is identical to the nominative.

So:

• nominative: разговор = conversation
• accusative: разговор = conversation

No visible change happens here.

This is very common with inanimate masculine nouns:

• Я вижу стол. = I see a table.
• Он читает журнал. = He is reading a magazine.
• Полицейский хочет прекратить разговор. = The police officer wants to end the conversation.

If the noun were feminine, for example, you would often see a different ending in the accusative.

It means to end the conversation, to stop the conversation, or to put an end to the conversation.

The verb прекратить is often used with things like:

• разговор = conversation
• спор = argument/dispute
• работу = work
• огонь = fire/shooting
• деятельность = activity

So прекратить разговор is a normal and natural expression for ending a conversation.

Depending on context, it could sound:

• neutral: end the conversation
• firm: stop the conversation
• official/formal: terminate the conversation

Yes. Russian word order is more flexible than English because case endings do a lot of the grammatical work.

The neutral order here is:

• Полицейский хочет прекратить разговор.

But other orders are possible, depending on emphasis:

• Разговор хочет прекратить полицейский.
  Emphasis on it is the police officer who wants to end the conversation.

• Прекратить разговор хочет полицейский.
  Emphasis on ending the conversation.

The original sentence is the most straightforward, neutral version for a learner.

Correct. Russian has no articles like English a/an and the.

So полицейский can mean:

• a police officer
• the police officer

And разговор can mean:

• a conversation
• the conversation

The exact meaning depends on context.

In isolation, Полицейский хочет прекратить разговор could be interpreted as either:

• A police officer wants to end a conversation
• The police officer wants to end the conversation

Usually the broader situation makes it clear.

The main stresses are:

• полице́йский
• хо́чет
• прекрати́ть
• разгово́р

A practical pronunciation guide:

• полице́йский ≈ puh-lee-TSEY-skee
• хо́чет ≈ KHO-chet
• прекрати́ть ≈ pree-kruh-TEET’
• разгово́р ≈ ruz-guh-VOR

A smooth full pronunciation might sound like:

пuh-lee-TSEY-skee KHO-chet pree-kruh-TEET’ ruzz-guh-VOR

A few notes:

• Unstressed о often sounds closer to a or a reduced vowel.
• The final ть in прекратить is soft.

Yes, you could, but it is not exactly the same.

• прекратить разговор = end/stop the conversation
• остановить разговор = literally stop the conversation

Прекратить разговор sounds more natural and idiomatic in many contexts, especially when you mean bring it to an end.

Остановить разговор is understandable, but it can sound a little less standard depending on context.

So for a learner, прекратить разговор is the better phrase to remember.

It is mostly neutral, with a slight tendency toward formal/official because of the verb прекратить.

Compare:

• Полицейский хочет прекратить разговор.
  Neutral, a bit official.

• Полицейский хочет закончить разговор.
  Also natural, slightly more everyday in some contexts.

• Полицейский хочет остановить разговор.
  Understandable, but less standard for this exact idea.

So if you see прекратить in official speech, news, or formal narration, that is very normal.