Learn Hardcore Russian: У моей сестры есть говорящий попугай в большой клетке. - My sister has a talking parrot in a big cage.

Literally this pattern is more like “By/at my sister there is a talking parrot,” but it simply means possession.
Моя сестра имеет… is grammatically correct, but in this context feels formal, bookish, or slightly off for normal conversation.

What case is сестры in У моей сестры and why does it end in -ы?

Сестры is in the Genitive singular.

The preposition у (“by/at”) requires the Genitive case, and we are talking about one sister, so:

Nominative (dictionary form): сестра (sister)
Genitive singular: сестры

Pattern: many feminine nouns ending in -а change to -ы / -и in the Genitive singular.

So:

у сестры = “at/by (my) sister” → used to mean “my sister has …”

Why is it моей сестры and not моя сестра?

The possessive adjective мой (“my”) must agree in gender, number, and case with the noun it modifies.

The noun is сестры:
- feminine
- singular
- Genitive case (because of у)

So мой must also be: feminine, singular, Genitive:

Masculine Nom.: мой
Feminine Nom.: моя
Feminine Gen.: моей

Therefore:

моя сестра – Nominative (subject form): “my sister”
у моей сестры – Genitive (after у): “my sister has / at my sister”

What is the function of есть here? Can it be left out?

In this structure у моей сестры есть…, the word есть roughly corresponds to English “there is / has”. It marks existence/possession:

У моей сестры есть говорящий попугай. → “My sister has a talking parrot.”

In spoken Russian, есть is often omitted when the existence is obvious from context or when we’re just stating a fact:

У моей сестры говорящий попугай.
This is also possible and would normally be understood as “My sister has a talking parrot,” but it sounds a bit more like a description or emphasis (e.g. contrasting with someone else’s non-talking parrot).

General rule of thumb:

With есть – neutral, straightforward statement of possession/existence.
Without есть – can sound more descriptive, contrastive, or contextual.

What case is попугай in, and why doesn’t it change form?

Попугай is in the Nominative singular.

In the construction у [Genitive] есть [Nominative], the thing possessed (the parrot) stands in the Nominative case, because grammatically it is the subject of the sentence:

У моей сестры есть говорящий попугай.
Literally: “At my sister there exists a talking parrot.”

Nominative singular of попугай is попугай, so the word keeps its dictionary form. If it were plural, it would be попугаи (Nominative plural):

У моей сестры есть говорящие попугаи. – “My sister has talking parrots.”

What exactly does говорящий mean, and how is it formed?

Говорящий is a present active participle of the verb говорить (“to speak, to talk”).

Formation (simplified):

Verb: говорить (to speak)
Remove -ить → говор-
Add participle ending -ящий → говорящий

Meaning:

Literally: “speaking” or “who is speaking”
As an adjective: “talking” (capable of speech)

So говорящий попугай = “a talking parrot / a parrot that talks.”

Participles like this behave like adjectives: they agree in gender, number, and case with the noun:

говорящий попугай (masc. nom. sg.)
говорящая птица (fem. nom. sg.)
говорящее животное (neut. nom. sg.)
говорящие попугаи (plural)

Could we say разговаривающий попугай instead of говорящий попугай? Is there any difference?

Both are understandable, but there is a nuance:

говорящий – from говорить, general “speaking, talking,” very common in the fixed phrase говорящий попугай (“talking parrot”).
разговаривающий – from разговаривать, which has more of a sense “to converse, to chat, to talk with someone.”

So:

говорящий попугай – the standard, natural phrase for a talking parrot (one that can pronounce words).
разговаривающий попугай – could suggest a parrot that engages in conversation, feels a bit more vivid/anthropomorphic, and is less set as an idiom.

For normal usage, говорящий попугай is the best choice.

Why is it в большой клетке and not в большая клетка or в большой клетку?

Because of:

The preposition в (“in”) indicating location.
Case and agreement rules.

When в means “in/inside (where?)” (location, not direction), it takes the Prepositional case.

The noun клетка (cage) is:

Nominative: клетка
Prepositional singular: клетке

So we need в клетке (“in the cage”).

The adjective большой (“big”) must agree with клетке in gender, number, and case:

Feminine, singular, Prepositional: большой

So the correct phrase is:

в большой клетке – “in a big cage”

В большая клетка uses the Nominative, which is wrong after в (with locational meaning).
В большой клетку mixes prepositional adjective with accusative noun; also incorrect in this meaning.

What case is клетке, and why does it end in -е?

Клетке is in the Prepositional singular.

Pattern for many feminine nouns ending in -ка:

Nominative singular: клетка (a cage)
Prepositional singular: клетке (“in/on/about the cage”)

The prepositional case is used after certain prepositions, including в and на, when they indicate location (where something is):

в клетке – in the cage
на улице – in the street / outside

Why is the adjective большой in that form? I thought большой was masculine.

The base form большой can be:

masculine Nominative: большой дом – big house
feminine Prepositional: о большой клетке – about a big cage
feminine Dative: к большой клетке – to a big cage
feminine Locative after в/на: в большой клетке – in a big cage

Adjectives in Russian have different endings depending on case and gender, but some forms coincide in spelling.

Here, большой is feminine, singular, Prepositional, agreeing with клетке (fem. sing. Prep.) after в:

в большой клетке – in a big cage

So even though it looks like masculine Nominative, in this sentence it actually functions as feminine Prepositional.

Can the adjective come after the noun, like попугай говорящий or клетка большая?

Yes, but the meaning or feel can change.

In Russian, normal descriptive adjectives usually come before the noun:

говорящий попугай – a talking parrot
большая клетка – a big cage

If you put the adjective after the noun:

попугай говорящий
More like “the parrot is talking / is a talking one” – it sounds more like a predicate or a contrast (“not just any parrot, but a talking one”).
клетка большая
Sounds like a whole mini-sentence (“the cage is big”) or a contrastive description (“the cage is big (as opposed to small)”).

So:

For neutral noun+adjective combinations, keep adjectives before the noun.
Postposed adjectives often sound emphatic, contrastive, or more sentence-like.

Can we change the word order of the whole sentence, for example: Говорящий попугай у моей сестры (есть).?

Yes, Russian word order is flexible, but the neutral, most common order for this meaning is:

У моей сестры есть говорящий попугай в большой клетке.

Other orders are possible and can add emphasis or change what feels “new” or “important”:

У моей сестры говорящий попугай в большой клетке.
(dropping есть) – slightly more descriptive or contrastive.
Говорящий попугай у моей сестры (есть) в большой клетке.
Sounds like you’re emphasizing “It is my sister who has a talking parrot in a big cage (not someone else)”, or answering “Who has the talking parrot in a big cage?”
В большой клетке у моей сестры есть говорящий попугай.
Emphasizes the location first: “In a big cage, my sister has a talking parrot.”

All are grammatically possible; the version in your sentence is the default, neutral one.

How would the sentence change if I want to say “My sister has two talking parrots in a big cage”?

You need to change the parrot part to dual / plural while keeping the structure:

У моей сестры есть два говорящих попугая в большой клетке.

Changes:

два – the numeral “two” (for masculine/neuter nouns).
говорящих – Genitive plural form of говорящий, agreeing with попугая after the numeral 2.
попугая – Genitive singular form used after два, три, четыре (this is a special rule of Russian numerals).

So the whole phrase два говорящих попугая functions as the thing she has: “two talking parrots.”