Мне нравится её светлая блузка.

Because Russian uses a different structure for to like.

• нравиться literally works more like to be pleasing
• So Мне нравится её светлая блузка is literally something like: Her light blouse is pleasing to me

That is why:

• мне = to me / I in this structure
• нравится = is pleasing
• её светлая блузка = the thing that is pleasing

So in Russian, the person who likes something is usually in the dative case, not the nominative.

Because with нравиться, the person experiencing the feeling is marked with the dative.

Here are the forms:

• я = I
• мне = to me

So:

• Мне нравится кофе = I like coffee
• Мне нравится эта книга = I like this book

This is one of the most important patterns to learn with нравиться:

• кому? = to whom?
• мне, тебе, ему, ей, нам, вам, им

Because the verb agrees with the thing being liked, and here that thing is блузка, which is:

• singular
• feminine

With нравиться, the verb agrees with the grammatical subject, not with the person in dative.

In this sentence, the subject is:

• её светлая блузка = her light blouse

Since it is singular, Russian uses нравится.

Compare:

• Мне нравится её блузка = I like her blouse
• Мне нравятся её блузки = I like her blouses

Because it is the grammatical subject of the sentence.

In the pattern мне нравится X, the thing liked is in the nominative:

• Мне нравится книга
• Мне нравится музыка
• Мне нравится её светлая блузка

Even though English says I like X, Russian is structurally closer to:

• X is pleasing to me

That is why блузка stays in the nominative.

Because the adjective must agree with блузка.

блузка is:

• feminine
• singular
• nominative

So the adjective also has to be:

• feminine
• singular
• nominative

That gives:

• светлая блузка

Compare the adjective endings:

• светлый = masculine singular nominative
• светлая = feminine singular nominative
• светлое = neuter singular nominative
• светлые = plural nominative

And in another case:

• светлую блузку = feminine singular accusative

But here nominative is needed, so светлая блузка is correct.

Here её means her.

So:

• её блузка = her blouse

A useful point: её does not change form for case in this possessive meaning.

Examples:

• её блузка = her blouse
• я вижу её блузку = I see her blouse
• я думаю о её блузке = I’m thinking about her blouse

The noun changes, but её stays the same.

Also, context usually makes it clear that this is possessive her, not the pronoun her as a direct object.

It can mean different things depending on context.

With clothing, светлый usually means:

• light-colored
• pale
• sometimes bright in the sense of not dark

So светлая блузка most naturally means:

• a light-colored blouse

For people, светлый can also mean:

• fair-haired
• light in coloring

For rooms or colors, it can mean:

• bright
• well-lit
• light-colored

So the exact English word depends on what noun it describes.

Yes. Russian word order is flexible, although the neutral order here is very natural:

• Мне нравится её светлая блузка.

You could also hear:

• Её светлая блузка мне нравится.
• Светлая блузка мне нравится.

The basic meaning stays the same, but the emphasis changes.

For example:

• Мне нравится её светлая блузка = neutral, everyday statement
• Её светлая блузка мне нравится = puts more focus on her light blouse
• Мне её светлая блузка нравится = can sound more contrastive or conversational

So word order in Russian often reflects focus and emphasis, not just grammar.

Yes, if the context already makes it clear whose blouse you mean, or if that information is not important.

• Мне нравится светлая блузка = I like the light blouse / I like a light blouse
• Мне нравится её светлая блузка = I like her light blouse

Adding её makes the blouse specifically belong to her.

Without её, the sentence is more general or depends more on context.

нравиться is imperfective.

That is the normal verb used for liking in general:

• Мне нравится эта песня = I like this song
• Тебе нравится Москва? = Do you like Moscow?

If you want a perfective idea such as to come to like or to begin to like, Russian often uses a different verb, for example:

• понравиться

Example:

• Мне понравилась её блузка = I liked her blouse / Her blouse appealed to me

So:

• нравится = like, be pleasing
• понравилась = came to be liked, appealed, liked on a particular occasion

Because Russian does not have a/an/the.

So блузка can mean:

• a blouse
• the blouse

Context tells you which is meant.

In Мне нравится её светлая блузка, the possessive её already makes it specific, so in English it naturally becomes:

• her light blouse

Russian relies on context, word order, and modifiers like её, этот, какой-то, and so on, instead of articles.