Głos naszej nauczycielki jest spokojny, więc nawet trudna wymowa wydaje się prostsza.

Because after głos (voice), Polish uses the genitive to show possession:

• głos nauczycielki = the teacher’s voice
• literally: voice of the teacher

So both words change into the genitive singular feminine:

• nasza → naszej
• nauczycielka → nauczycielki

That is why naszej nauczycielki means of our teacher.

Because it describes głos, and głos is:

• masculine
• singular
• in the nominative

So the adjective must match it:

• głos → masculine singular
• spokojny → masculine singular nominative

This is basic adjective agreement in Polish: adjectives match the noun in gender, number, and case.

In the present tense, Polish often omits to be in some sentence types, but with adjectives like this, jest is very normal and natural:

• Głos naszej nauczycielki jest spokojny. = Our teacher’s voice is calm.

You may sometimes hear omission in very informal or poetic styles, but here jest is the standard choice.

So for learners, it is best to think:

• X jest spokojny = X is calm

Więc means so, therefore, or as a result.

It connects the two parts of the sentence:

• Głos naszej nauczycielki jest spokojny = the cause
• więc nawet trudna wymowa wydaje się prostsza = the result

So the logic is:

Her voice is calm, so even difficult pronunciation seems simpler.

Other similar connectors include:

• dlatego = therefore / for that reason
• więc = so

In this sentence, więc sounds very natural.

Because wymowa (pronunciation) is:

• feminine
• singular
• nominative

So the adjective also has to be feminine singular nominative:

• trudny → masculine
• trudna → feminine
• trudne → neuter

That is why we get:

• trudna wymowa = difficult pronunciation

Wydaje się means seems or appears.

The base verb is wydawać się, which is a fixed reflexive verb meaning to seem. Here się is not really translated as itself. It is just part of the verb.

So:

• wydawać can mean to give out / publish / spend in other contexts
• wydawać się means to seem

Examples:

• To wydaje się łatwe. = That seems easy.
• On wydaje się zmęczony. = He seems tired.

So in your sentence:

• wymowa wydaje się prostsza = the pronunciation seems simpler

Prostsza is the comparative form of prosta (simple).

Polish often forms comparatives in two ways:

1. synthetic comparative: one-word form
   
   • prosta → prostsza
2. analytic comparative: bardziej + adjective
   
   • bardziej prosta

For many common adjectives, the one-word comparative is much more natural. So:

• prostsza = simpler

That is why wydaje się prostsza sounds better than wydaje się bardziej prosta here.

Good question. Polish, like English, does not always need to state the second part of a comparison if it is understood from context.

So:

• wydaje się prostsza = seems simpler

The sentence does not explicitly say:

• simpler than usual
• simpler than expected
• simpler than it really is

That comparison is left implicit. This works in English too:

• It seems easier.

You do not always need to add than before or than I thought.

Nawet means even.

It adds emphasis and shows that something surprising is true:

• nawet trudna wymowa = even difficult pronunciation

The idea is that the teacher’s calm voice helps so much that even something difficult feels simpler.

Its position before trudna wymowa is very natural, because it emphasizes that whole noun phrase.

Yes, Polish word order is fairly flexible, but the original order is neutral and natural:

• Głos naszej nauczycielki jest spokojny, więc nawet trudna wymowa wydaje się prostsza.

You can move things around for emphasis, but not all versions sound equally natural. For example:

• Nawet trudna wymowa wydaje się prostsza, bo głos naszej nauczycielki jest spokojny.
• This changes the focus a bit and uses bo instead of więc.

In the original sentence:

• first comes the reason
• then the result

That makes the sentence easy to follow.

Because wymowa usually refers to:

• pronunciation
• the way sounds are pronounced

It does not usually mean voice; that is głos.

So in this sentence:

• głos = voice
• wymowa = pronunciation

That distinction is important:

• Ma miły głos. = She has a nice voice.
• Ma dobrą wymowę. = She has good pronunciation.

Both, in a way.

The noun nauczycielka is the specifically female form of teacher. So the sentence tells you the teacher is a woman.

Compare:

• nauczyciel = male teacher / teacher in a masculine form
• nauczycielka = female teacher

Because the noun is feminine, the possessive adjective also takes the feminine genitive form:

• naszego nauczyciela = of our male teacher
• naszej nauczycielki = of our female teacher

So yes, the grammar reflects the fact that the teacher is female.

No, not in this meaning.

To express possession with voice, Polish uses the genitive:

• głos naszej nauczycielki

Using od usually means from, not possession:

• list od nauczycielki = a letter from the teacher

But głos od nauczycielki would sound wrong if you mean the teacher’s voice.

So remember:

• possession here → genitive
• głos kogo? → nauczycielki