Скоростной интернет работает хорошо.

Скоростной means high-speed. It comes from скорость (speed), so it describes something connected with speed or fast transmission.

In this sentence, скоростной интернет means high-speed internet.

A learner may wonder why Russian does not use быстрый интернет here. Быстрый means fast, and people may understand it, but скоростной интернет is the more natural and standard way to say high-speed internet.

Because it agrees with интернет, which is a masculine singular noun in the nominative case.

So:

• скоростной = masculine singular nominative adjective
• интернет = masculine singular nominative noun

Russian adjectives must agree with the nouns they describe in:

• gender
• number
• case

That is why you get скоростной интернет.

In Russian, интернет is treated as a masculine noun. That is why you say:

• скоростной интернет
• новый интернет
• интернет работает

Many borrowed nouns in Russian are assigned a grammatical gender, and интернет ended up being masculine.

A good clue is that many consonant-ending nouns are masculine in Russian, and интернет ends in a consonant.

Yes, работать literally means to work, but in Russian it is also very commonly used for machines, systems, devices, services, and technology.

So интернет работает хорошо means something like:

• the internet works well
• the internet is functioning well

This is very natural Russian. It does not mean the internet is doing a job like a person; it means it is functioning properly.

Because the subject is интернет, which is singular.

• интернет = singular
• therefore the verb must also be singular: работает

If the subject were plural, then you would use работают.

For example:

• Компьютеры работают хорошо = The computers work well

Работает is:

• 3rd person singular
• present tense
• from the verb работать

So it means:

• works
• is working
• does work

depending on context.

Here, Скоростной интернет работает хорошо is best understood as High-speed internet works well or The high-speed internet is working well.

Because хорошо is an adverb, and it modifies the verb работает.

It answers the question How does it work? → Хорошо = well

Compare:

• хороший интернет = good internet
  Here хороший is an adjective describing the noun интернет.

• интернет работает хорошо = the internet works well
  Here хорошо is an adverb describing the verb работает.

This is the same difference as English good vs well.

Yes, but it means something different.

• Скоростной интернет работает хорошо = High-speed internet works well
• Скоростной интернет хороший = High-speed internet is good

The first sentence focuses on function/performance. The second focuses on a more general evaluation.

Russian often prefers работает хорошо when talking about whether technology, systems, or connections are functioning properly.

No, Russian word order is fairly flexible, although some orders sound more natural than others depending on emphasis.

The neutral order is:

• Скоростной интернет работает хорошо.

You could also say:

• Интернет работает хорошо.
• Хорошо работает скоростной интернет.
• Скоростной интернет хорошо работает.

These alternatives may shift the emphasis a little, but the basic meaning stays similar.

For a learner, the given order is the safest and most natural neutral choice.

Russian has no articles like English a and the.

So Скоростной интернет работает хорошо could mean:

• High-speed internet works well
• The high-speed internet works well
• sometimes even A high-speed internet connection works well, depending on context

Russian relies on context, word order, and the situation to show whether something is definite or indefinite.

A natural pronunciation is:

• скоростно́й интерне́т рабо́тает хорошо́

Stress:

• скоростно́й
• интерне́т
• рабо́тает
• хорошо́

A learner should be careful especially with:

• скоростно́й — stress on the final -ой
• интерне́т — stress on the last syllable
• хорошо́ — stress on the last syllable

It is understandable and correct, but in everyday modern usage, many speakers more often say:

• высокоскоростной интернет = high-speed internet
• быстрый интернет = fast internet in less formal speech

So скоростной интернет работает хорошо is grammatical and clear, but высокоскоростной интернет работает хорошо may sound more standard in many contexts.

Still, for learning purposes, скоростной интернет is perfectly useful and easy to understand.