Сообщите диспетчеру, предупредите соседей и согласуйте время.

It is an imperative sentence: a list of instructions or commands.

The three commands are:

• Сообщите
• предупредите
• согласуйте

So the speaker is telling someone to do three things.

All three are imperative verb forms meaning tell/report, warn/notify, and agree/coordinate.

More specifically, they are the plural/formal imperative forms. In Russian, this form is used for:

• one person formally (like you in a polite instruction), or
• more than one person

So this sentence could be addressed either to one person politely or to several people.

That depends on the verb they come from.

• сообщить → сообщи → сообщите
• предупредить → предупреди → предупредите
• согласовать → согласуй → согласуйте

Verbs like согласовать often form the imperative with -уй / -уйте.

So the difference is not random: it comes from the verb’s stem and infinitive pattern.

Because сообщить usually takes the pattern:

• сообщить кому? что?
• report/tell something to someone

So the person receiving the information goes into the dative case.

Here:

• диспетчер = dispatcher
• диспетчеру = to the dispatcher

That is why you see диспетчеру, not диспетчер.

Because предупредить takes a direct object:

• предупредить кого?
• warn/notify whom?

That means the noun goes into the accusative case.

For animate plural nouns in Russian, the accusative plural looks like the genitive plural. So:

• соседи = neighbors
• соседей = neighbors (as a direct object)

So предупредите соседей means warn/notify the neighbors.

It is accusative singular, because согласовать takes a direct object:

• согласовать что?
• agree/coordinate what?

So:

• согласуйте время = agree/coordinate the time

The reason время looks unchanged is that for this noun, the nominative and accusative singular are the same:

• nominative: время
• accusative: время

Russian instructions often use the perfective imperative when the speaker wants the action to be completed.

Here the idea is:

• report it,
• notify them,
• agree on the time,

as finished actions.

The verbs are:

• сообщить rather than сообщать
• предупредить rather than предупреждать
• согласовать rather than согласовывать

If you used imperfective imperatives instead, it could sound more like an ongoing, repeated, or general process.

It can be either:

• one person formally
• several people

Russian uses the same imperative ending here for both.

So without more context, Сообщите... could mean:

• Please report... to one person politely, or
• Report... to a group

If you were speaking to one person informally, the sentence would be:

Сообщи диспетчеру, предупреди соседей и согласуй время.

Compare:

• formal/plural: сообщите, предупредите, согласуйте
• informal singular: сообщи, предупреди, согласуй

So the difference is mainly in the imperative ending.

Literally, it is something like coordinate/agree the time.

In natural English, you usually say agree on a time or coordinate the time. Russian often does not need the same preposition that English uses.

Also, Russian can add another phrase if needed, for example:

• согласуйте время с соседями
• согласуйте время с диспетчером

Here с кем? means with whom? But in your sentence, that part is simply left understood from context.

Yes, Russian word order is fairly flexible, but the given order is natural and clear for a list of instructions.

Сообщите диспетчеру, предупредите соседей и согласуйте время sounds like a straightforward sequence of steps.

You could rearrange parts for emphasis, but the original version is probably the most neutral and practical.

Because this is a list of three commands:

• Сообщите диспетчеру
• предупредите соседей
• и согласуйте время

Russian punctuation here works much like English:

• a comma separates earlier items in the list
• и joins the last item, so there is normally no comma before it

So the punctuation is completely standard.

Yes, stress is helpful because Russian stress is not always predictable. The main stresses are:

• сообщИте
• диспЕтчеру
• предупредИте
• соседЕй
• согласУйте
• врЕмя

If you learn the stressed syllables early, your pronunciation will sound much more natural.