Во втором куплете солист поёт короткое соло, а потом поёт весь ансамбль.

Russian sometimes uses во instead of в to make pronunciation easier.
Here, в втором would be awkward because of the consonant cluster at the beginning, so Russian prefers:

• во втором куплете

This is a very common pattern:

• во вторник
• во Франции
• во время

So the extra о is mainly for ease of pronunciation, not a change in meaning.

Because after в / во meaning in or during, Russian often uses the prepositional case when talking about location or position.

So:

• второй куплет = the second verse (dictionary form)
• во втором куплете = in the second verse

Both words change because второй is an adjective modifying куплет, and adjectives must agree with the noun in case, gender, and number.

Here both are:

• prepositional
• masculine
• singular

So:

• второй → втором
• куплет → куплете

Куплет means a verse of a song. In music-related contexts, it is the standard word for a verse section.

So:

• во втором куплете = in the second verse

It is not the same as a poetic stanza in every context, although the translation can sometimes overlap.

Russian has no articles. There is no direct equivalent of a / an / the.

So:

• солист can mean a soloist or the soloist
• соло can mean a solo or the solo
• ансамбль can mean an ensemble or the ensemble

You figure out which one is meant from context. In this sentence, English naturally uses the in translation, but Russian does not need any article.

Yes. Петь соло or петь соло / короткое соло is normal and means to sing a solo.

Here:

• солист = the soloist
• поёт = sings
• короткое соло = a short solo

So literally:
The soloist sings a short solo.

Russian also allows other verbs depending on style, for example:

• исполняет соло = performs a solo

But поёт соло is perfectly natural when the solo is sung.

It is in the accusative case, because it is the direct object of поёт.

The basic form is:

• короткое соло

And the accusative is the same here because:

• соло is inanimate
• it is neuter singular
• many neuter inanimate nouns have the same form in nominative and accusative

So although the form does not visibly change, grammatically it is the object of the verb.

Also, соло is an indeclinable loanword, so the noun itself stays соло in all cases, while the adjective changes as needed.

Because соло is an indeclinable noun in Russian. It is a borrowed word, and Russian usually keeps it unchanged in different cases.

So you can get things like:

• это соло
• короткое соло
• в этом соло
• без этого соло

The noun соло stays the same, while any adjective or pronoun around it shows the grammatical case.

Russian often repeats the verb for clarity and rhythm, especially when describing a sequence of actions.

So:

• солист поёт короткое соло, а потом поёт весь ансамбль

means:

• the soloist sings a short solo, and then the whole ensemble sings

The repeated поёт makes the structure balanced and explicit.

Could Russian omit it? Sometimes Russian can omit repeated elements, but here repeating поёт sounds natural and clear. It helps avoid any hesitation about what exactly the ensemble is doing.

Because ансамбль is a singular noun. It means ensemble/group, which is grammatically singular even though it refers to multiple people.

So Russian treats it like this:

• весь ансамбль поёт = the whole ensemble sings

not:

• весь ансамбль поют

The subject is singular, so the verb is singular:

• ансамбль поёт

If you wanted a plural subject, you would need a plural noun, for example:

• все участники ансамбля поют = all the members of the ensemble sing

Because ансамбль is masculine singular, so the adjective must agree with it.

• весь ансамбль = the whole ensemble

Here:

• весь = masculine singular
• ансамбль = masculine singular

Все is plural, so it cannot modify ансамбль directly.

Compare:

• весь ансамбль = the whole ensemble
• все музыканты ансамбля = all the ensemble’s musicians

Both can often be translated as and then, but а and и are not exactly the same.

• и usually simply adds information: and
• а often marks a transition, contrast, or shift to a new stage

In this sentence, а потом feels very natural because the focus shifts from one performer to another:

• first, the soloist sings
• then, the whole ensemble sings

So а потом nicely signals that change of scene or role. It is not a strong contrast like but, but it is more of a transition than simple addition.

Russian word order is flexible. Both are possible, but they can sound slightly different in emphasis.

• весь ансамбль поёт puts the subject first, more neutral
• поёт весь ансамбль can sound a bit more like then it’s the whole ensemble that sings

Here the order fits the rhythm of the sentence well and keeps parallel structure with the earlier солист поёт.

So it is not a different tense or grammar rule—just a word order choice with a slightly different emphasis.

Yes. Потом here means then / afterwards / after that.

So:

• а потом = and then / and afterwards

It tells you the order of events:

1. the soloist sings
2. afterwards, the whole ensemble sings

Поёт is pronounced roughly pa-YOT.

The letter ё always shows a stressed yo sound. That is why the stress is clear here:

• поёт

The verb comes from петь = to sing.

Forms include:

• я пою = I sing
• он / она поёт = he / she sings
• они поют = they sing

In normal printed Russian, ё is sometimes written as е, but it is still understood as ё from context. For learners, it is very helpful to remember the real pronunciation: поёт, not поет with a plain e sound.