У этой лошади длинная грива и тёплая шерсть.

In Russian, possession is very often expressed with the pattern у + genitive + something in the nominative.

So У этой лошади длинная грива и тёплая шерсть literally works like:

At this horse, there is a long mane and warm fur.

That is the normal Russian way to say This horse has a long mane and warm fur.

This is much more natural in Russian than trying to copy the English structure with has.

Because the preposition у requires the genitive case.

• эта лошадь = this horse (nominative)
• этой лошади = of this horse / at this horse (genitive after у)

So:

• эта лошадь = the horse as the subject
• у этой лошади = this horse in a possession construction

A learner can think of у as forcing the following noun phrase to change form.

Лошадь is a feminine noun ending in -ь. Nouns of this type have special case endings.

Its forms include:

• лошадь — nominative singular
• лошади — genitive singular
• лошади — dative singular
• лошадью — instrumental singular

So here, after у, we need the genitive singular, which is лошади.

This can be confusing because лошади is also the dative singular form, but in this sentence the preposition у tells you it must be genitive.

Because у only affects этой лошади.

The things being possessed — длинная грива and тёплая шерсть — stay in the nominative case. In this kind of Russian possession pattern, the possessed things are normally nominative.

So the structure is:

• у этой лошади — possessor, in genitive
• длинная грива и тёплая шерсть — what the horse has, in nominative

They agree with the nouns they describe in gender, number, and case.

• длинная matches грива
• тёплая matches шерсть

Both грива and шерсть are feminine singular nominative, so the adjectives are also feminine singular nominative.

That is why you see:

• длинная грива
• тёплая шерсть

If the noun changed case, the adjective would change too.

Not necessarily. Лошадь is a grammatically feminine noun, so words that agree with it use feminine forms.

That is why you get:

• эта лошадь
• у этой лошади

This is grammatical gender, not always biological sex.

However, in some contexts лошадь can suggest a horse in a general sense or sometimes a mare. If Russian wants to specify a male horse, it may use a different noun, such as конь or жеребец, depending on context.

So in this sentence, the feminine forms come from the noun лошадь, not necessarily from the real animal’s sex.

Russian often does not use a direct equivalent of English has in everyday possession sentences.

Instead, it uses the у + genitive structure. Also, Russian often omits a present-tense linking verb.

A fuller version could be:

У этой лошади есть длинная грива и тёплая шерсть.

Here есть means something like there is / has.

But in descriptive sentences like this one, leaving out есть is very natural. Without есть, the sentence sounds more like a straightforward description of the horse’s features.

So both can be possible, but the version without есть is perfectly normal.

Grammatically, you could say something with имеет, because иметь means to have. But it is usually less natural here.

For body parts, animal features, and ordinary possession, Russian strongly prefers:

у + genitive

So:

• natural: У этой лошади длинная грива...
• less natural / more formal: Эта лошадь имеет длинную гриву...

Иметь often sounds more formal, bookish, technical, or emphatic. For normal description of a horse’s physical traits, у этой лошади... is the idiomatic choice.

Шерсть refers to an animal’s fur, coat, or hair covering.

For a horse, English might say:

• coat
• hair
• sometimes fur in a broad explanatory sense

So тёплая шерсть means the horse has a warm hair/fur coat.

A useful point: шерсть is usually a mass noun in Russian, like a material or covering, not a countable set of separate hairs.

Because шерсть is normally used as an uncountable / mass noun.

Russian treats it like a substance or covering:

• тёплая шерсть = warm coat/fur/hair

English often does something similar with words like hair:

• She has long hair, not usually long hairs

So singular шерсть is exactly what you would expect here.

И simply means and.

It joins the two noun phrases:

• длинная грива
• тёплая шерсть

So the horse has two described features:

1. a long mane
2. a warm coat/fur

The given word order is natural and neutral:

У этой лошади длинная грива и тёплая шерсть.

It starts with the possessor, then gives the features.

Russian word order is flexible, so other orders are possible, but they change emphasis. For example:

• Длинная грива и тёплая шерсть у этой лошади.
  This puts more focus on the features.

• Тёплая шерсть и длинная грива у этой лошади.
  This emphasizes шерсть first.

The original version is the most straightforward if you are just describing the horse.

Yes, ё matters here.

• тёплая is pronounced with a yo sound: roughly TYOP-laya
• The stressed syllable is тёп-

In Russian writing, ё is sometimes replaced by е, especially in informal texts, so you may also see теплая. But the correct pronunciation is still тёплая, not теплая with a plain e sound.

So for learners, it is helpful to remember that ё tells you both the pronunciation and the stress more clearly.