soko ha sizuka desu.

They are usually added only for learners.

In normal Japanese, this sentence is written as:

そこは静かです。

Japanese is normally written without spaces, and readers figure out the word boundaries from the writing system and context.

When は is used as a particle, it is pronounced wa.

So in this sentence:

• written: そこは静かです
• pronounced: soko wa shizuka desu

The particle keeps the historical spelling は, but its pronunciation in this role is wa.

は marks the topic of the sentence.

Here, そこは means something like:

• as for there
• that place
• speaking of there

Then the rest of the sentence says something about that topic:

• 静かです = is quiet

So the structure is basically:

• Topic: そこは
• Comment about the topic: 静かです

そこ refers to a place near the listener or a place that has just been mentioned.

It belongs to the common location set:

• ここ = here, near the speaker
• そこ = there, near the listener
• あそこ = over there, away from both

So そこ is not just any there; it has a specific position in relation to the speaker and listener.

静か is a na-adjective.

In Japanese, there are two major adjective types learners often meet:

• i-adjectives like 暑い
• na-adjectives like 静か

静か behaves a little differently from an English adjective. It can describe something, but grammatically it patterns like a na-adjective.

Because な is only used when a na-adjective comes directly before a noun.

For example:

• 静かな町 = a quiet town

But in your sentence, 静か is at the end as the predicate, followed by です:

• そこは静かです。

So no な is used there.

です makes the sentence polite and works like a polite copula.

In this sentence, it helps make 静か into a complete polite statement:

• 静かです = is quiet

A less polite/plain version would be:

• そこは静かだ。

In beginner materials, です is often translated as is, but it is better to think of it as a polite sentence-ending form that links the description to the topic.

Japanese often leaves out words that are understood from context.

English usually needs an explicit subject like it or that place, but Japanese often does not. Here, once そこ is marked as the topic, that is enough.

So Japanese does not need to say something like:

• そこはそこが静かです

That would be unnatural. The topic already tells you what the sentence is about.

Sometimes, but the nuance changes.

• そこは静かです。 = As for there, it is quiet.
• そこが静かです。 = That place is the quiet one / There is what is quiet

は is the natural choice when you are simply talking about a place as the topic.

が tends to sound more specific or contrastive, as if you are identifying which place is quiet.

So for a basic neutral statement, は is usually the better choice.

Yes. The natural order is:

• そこは
  • 静かです

Japanese is often described as flexible, but that does not mean you can arrange words freely in any order. In this sentence, the topic comes first, and the description comes after it.

So:

• そこは静かです。 = natural
• 静かです、そこは。 = possible in special spoken contexts, but not the normal beginner pattern
• そこです静か。 = incorrect

A good beginner pattern to remember is:

• Topic + は + description + です

It can be either, depending on context.

そこは静かです。 could mean:

• that place is generally quiet
• that place is quiet right now

Japanese often leaves this kind of distinction to context unless more detail is added.

For example:

• そこはいつも静かです。 = it is always quiet there
• そこは今静かです。 = it is quiet there now