Стандартный вычет — это налоговый вычет.

In Russian, the verb to be is usually omitted in the present tense.

So instead of saying something like Стандартный вычет есть налоговый вычет, Russian normally says:

Стандартный вычет — это налоговый вычет.

This is the standard way to say X is Y in the present tense.

A few useful comparisons:

• Он врач. = He is a doctor.
• Москва — это столица России. = Moscow is the capital of Russia.

So the sentence is completely normal even though there is no separate word for is.

Here, это does not really mean this in the usual pointing sense.

In this kind of sentence, это works more like a linking element that helps connect the two nouns:

• Стандартный вычет = the subject
• налоговый вычет = what it is being identified as

So in this sentence, это is functioning more like that is / is / namely than literal this.

Compare:

• Это книга. = This is a book.
  Here это really can mean this.
• Москва — это столица России. = Moscow is the capital of Russia.
  Here это is mainly a connector.

So in your sentence, think of это as part of the pattern for saying A is B.

The dash is standard Russian punctuation in many sentences where one noun is being equated with another noun, especially in definitions or explanations.

So:

• Стандартный вычет — это налоговый вычет.

has the feel of a definition:

• A standard deduction is a tax deduction.

The dash helps mark the break between the topic and the explanation.

This is especially common in formal or explanatory writing.

Because this is a basic identification/definition sentence in the present tense, both noun phrases are in the nominative case:

• Стандартный вычет — nominative
• налоговый вычет — nominative

Russian often uses the nominative for both parts in sentences of the type X is Y, especially with это.

So here the structure is essentially:

• [Nominative noun phrase] — это [nominative noun phrase]

That is why both instances of вычет stay in the same form.

Because both are adjectives modifying the masculine noun вычет.

Вычет is:

• masculine
• singular
• nominative

So the adjectives agreeing with it must also be:

• masculine
• singular
• nominative

That gives:

• стандартный вычет
• налоговый вычет

This is adjective-noun agreement, which is very important in Russian.

It is repeated because the sentence is defining one type of deduction as belonging to a broader category.

• стандартный вычет = a standard deduction
• налоговый вычет = a tax deduction

So the idea is:

• a standard deduction is a kind of tax deduction

Russian often repeats the noun in this kind of definition because it makes the classification clear.

If you removed the second вычет, the sentence would not work properly:

• Стандартный вычет — это налоговый.
  This sounds incomplete here.

So the repetition is natural and useful.

Yes, you can say:

Стандартный вычет — налоговый вычет.

This is also grammatical, and it sounds a bit more compact or formal, almost like a dictionary-style definition.

Adding это makes the sentence slightly more explicit and conversational:

• Стандартный вычет — налоговый вычет.
• Стандартный вычет — это налоговый вычет.

Both are possible, but the version with это is very common in explanations and teaching language.

Yes, but the emphasis may change.

The original sentence:

Стандартный вычет — это налоговый вычет.

puts the focus on стандартный вычет as the thing being defined.

If you reverse it:

Налоговый вычет — это стандартный вычет.

that means something different:

• A tax deduction is a standard deduction

That is not the same idea. It suggests that every tax deduction is a standard deduction, which is a different statement.

So word order matters because it affects what is being defined as what.

Russian has no articles.

So Russian does not mark the difference between:

• a standard deduction
• the standard deduction

using separate words like English does.

Instead, Russian relies on:

• context
• word order
• stress
• the overall situation

In this sentence, English naturally uses an article when translating, but Russian does not need one.

The stress is:

• стандартный → станда́ртный
• вычет → вы́чет
• налоговый → нало́говый

So the whole sentence is approximately:

станда́ртный вы́чет — э́то нало́говый вы́чет

For an English speaker, a useful thing to notice is that Russian stress is important and can be unpredictable, so it is worth learning each word together with its stress.

No. In Russian, this is a dash (тире), not a hyphen (дефис).

In your sentence:

• Стандартный вычет — это налоговый вычет.

the long mark is punctuation connecting parts of the sentence.

A hyphen is used inside a word or between tightly connected parts, not for this kind of sentence structure.

So here you should think:

• — = dash, used for sentence structure
• - = hyphen, used inside word combinations

Yes, it reads very much like a definition or classification.

It has the pattern:

• X — это Y

which is one of the most common Russian ways to define something.

So even if the exact meaning is already known, the grammar here is useful because you can reuse the same pattern in many other sentences:

• Банк — это финансовая организация.
• Рубль — это валюта России.
• Глагол — это часть речи.

Your sentence works the same way.