Дети не доели кашу, а я не допила кофе, потому что мы спешили.

Here до- adds the idea of finishing something all the way to the end.

• есть = to eat
• доесть = to finish eating
• пить = to drink
• допить = to finish drinking

So:

• не доели кашу = they did not finish the porridge
• не допила кофе = I did not finish the coffee

This is different from simply не ели or не пила, which would mean the action did not happen, or at least is not presented as happening.

Because Russian past tense agrees with the subject in number and, in the singular, also gender.

• дети is plural, so the verb is доели
• я is singular, and допила shows that the speaker is female

If the speaker were male, it would be:

• а я не допил кофе

So the sentence as written sounds like it is spoken by a woman.

Because кашу is the accusative singular form of каша.

Here кашу is the direct object of the verb не доели. In Russian, direct objects often go into the accusative case.

• nominative: каша
• accusative: кашу

This is very normal for a feminine noun ending in -а.

Because кофе is usually treated as an indeclinable noun in standard Russian, so its form stays the same in different cases.

So in this sentence:

• nominative: кофе
• accusative: кофе

Also, кофе is traditionally masculine in standard Russian, even though it ends in -е.

That is a very good question. Russian negation can sometimes take the genitive, but it does not have to.

Here кашу is natural because the porridge is being treated as a specific, concrete thing that the children were eating but did not finish.

So:

• не доели кашу = they did not finish the porridge

Using genitive here, каши, would sound less neutral and could suggest a more indefinite or partitive idea. In modern everyday Russian, the accusative is very common with negation when the object is specific.

Because а often links two clauses with a contrast or comparison, even a mild one.

Here the meaning is something like:

• the children did not finish their porridge, and as for me, I did not finish my coffee

So а feels more natural than и, because the speaker is shifting from the children to I.

• и would sound like simple addition
• а sounds like a natural contrast or change of topic

English often uses and in both situations, but Russian distinguishes them more clearly.

Because спешили is imperfective, and that fits the meaning here: it describes the background situation or ongoing circumstance.

• мы спешили = we were in a hurry / we were hurrying

This explains why they did not finish eating and drinking. It is not presented as a single completed action, but as a state that was happening at the time.

So the pattern is:

• не доели / не допила = failed to complete something
• мы spешили = background reason

Because negation does not prevent a verb from being perfective.

In this sentence, the perfective verbs доесть and допить are useful because the point is about completion. The sentence is not saying that no eating or drinking happened at all. It is saying that the expected completion did not happen.

So:

• не доели = did not finish
• не допила = did not finish

Perfective under negation often means the result was not achieved.

Both can be translated similarly in some contexts, but the nuance is different.

• не доели кашу strongly suggests that they started eating it but left some
• не съели кашу can simply mean they did not eat up the porridge, and it does not emphasize as clearly that they had already begun

So до- is especially good when you want to show partial completion:

• some was eaten
• not all of it was finished

The same applies to:

• не допила кофе = did not finish the coffee
• не выпила кофе = did not drink the coffee up, which may be less specifically about stopping partway through

No, Russian word order is flexible, but the version given is a very natural, neutral one.

• Дети не доели кашу, а я не допила кофе, потому что мы спешили.

It presents the information in a straightforward way:

1. subject
2. verb
3. object
4. contrasting clause
5. reason

Other word orders are possible for emphasis, for example if you want to stress кашу or кофе, but the original sentence is the most neutral and learner-friendly version.

Because Russian has no articles.

English needs words like the and a, but Russian usually expresses definiteness through context instead.

So кашу can mean:

• the porridge
• some porridge

And кофе can mean:

• the coffee
• some coffee

In this sentence, the context makes it clear that we are talking about the food and drink they were already having.

Yes. Мы спешили means we were in a hurry, so it gives a shared reason for both parts of the sentence:

• the children did not finish the porridge
• I did not finish the coffee
• because we were in a hurry

If the speaker wanted to say that only the children were in a hurry, or only the speaker was in a hurry, Russian would use a different subject in that final clause.