Moja kuzynka powiedziała, że przyjedzie jutro rano.

Because kuzynka is a feminine noun, so the possessive adjective must also be in the feminine form.

• mój = my, masculine
• moja = my, feminine
• moje = my, neuter

So moja kuzynka means my female cousin.

They mean cousin, but they differ by gender:

• kuzynka = female cousin
• kuzyn = male cousin

Since the sentence is about a woman, Polish uses kuzynka.

Powiedziała is the past tense form of powiedzieć and it agrees with a feminine subject.

Polish past tense changes according to gender in the singular:

• powiedział = he said
• powiedziała = she said
• powiedziało = it said, neuter

So Moja kuzynka powiedziała means My cousin said with the verb clearly showing that the speaker is talking about a woman.

In Polish, a comma is normally required before że when it introduces a subordinate clause.

So in:

Moja kuzynka powiedziała, że przyjedzie jutro rano.

the comma separates:

• the main clause: Moja kuzynka powiedziała
• the subordinate clause: że przyjedzie jutro rano

This is standard Polish punctuation.

Że means that and introduces the content of what was said.

So:

• powiedziała, że... = said that...

In English, that is often omitted:

• My cousin said she would arrive tomorrow morning

But in Polish, że is very commonly used and sounds natural here.

Przyjedzie means will arrive / will come in the future.

It comes from the verb przyjechać, which means to arrive by vehicle / to come by some means of transport. So it suggests coming by car, train, bus, etc., rather than simply coming on foot.

Compare:

• przyjechać → przyjedzie = will arrive, will come by transport
• przyjść → przyjdzie = will come, will arrive on foot or more generally

Przyjechała would be she arrived in the past, so it would not fit with jutro rano.

This is because przyjechać is a perfective verb.

In Polish, perfective verbs do not normally have a true present tense. Their present-looking forms actually refer to the future.

So:

• przyjedzie literally looks like a present form
• but it means she will arrive

This is very common in Polish:

• napisze = he/she will write
• zrobi = he/she will do, make
• powie = he/she will say

Jutro rano means tomorrow morning.

It is a very natural Polish time expression, and no preposition is needed.

Compare:

• jutro = tomorrow
• rano = in the morning / morning

Together:

• jutro rano = tomorrow morning

Similar expressions:

• dzisiaj rano = this morning
• wczoraj rano = yesterday morning

So this is just the normal idiomatic way to say it.

Yes. Polish word order is more flexible than English because endings show grammatical relationships.

The neutral order here is:

Moja kuzynka powiedziała, że przyjedzie jutro rano.

But other orders are possible, depending on emphasis. For example:

• Moja kuzynka powiedziała, że jutro rano przyjedzie.
• Jutro rano moja kuzynka powiedziała, że przyjedzie.
  This changes the meaning emphasis and may sound less natural in this context.

Usually, jutro rano is kept near the verb it belongs to, but Polish allows movement for focus or style.

You could say Kuzynka powiedziała, but moja kuzynka is more natural if you mean my cousin and want to identify whose cousin you are talking about.

Polish often drops words when the meaning is already clear from context, but including moja makes the sentence more explicit.

So:

• Moja kuzynka powiedziała... = My cousin said...
• Kuzynka powiedziała... = The cousin / my cousin said..., depending on context

Because Polish usually does not need subject pronouns when the verb form already shows the person, and the subject is clear from context.

In this sentence, the listener already knows that the person being discussed is moja kuzynka, so saying ona would usually be unnecessary.

Natural:

• Moja kuzynka powiedziała, że przyjedzie jutro rano.

Also possible, but more emphatic:

• Moja kuzynka powiedziała, że ona przyjedzie jutro rano.

Adding ona may suggest contrast or emphasis, such as she will come, not someone else.

Yes. They are related but not the same.

• powiedziała = she said; usually one completed act of saying
• mówiła = she was saying / she used to say / she said in a more ongoing or repeated sense, depending on context

In this sentence, powiedziała is the natural choice because it refers to one completed statement: she said that she would arrive tomorrow morning.

A rough English-friendly pronunciation is:

• powiedziała ≈ po-vye-JA-wa
• że ≈ zhe
• przyjedzie ≈ pshi-YED-jye

A few useful sound notes:

• w in Polish sounds like English v
• dzia in powiedziała sounds roughly like ja with a soft d before it
• ż sounds like the s in measure
• przy is tricky; it is somewhat like pshi
• dzie is a soft sound, roughly jye

The stress is usually on the second-to-last syllable:

• po-wie-dzia-ła
• przy-je-dzie

Not normally. In this sentence, przyjedzie clearly points to the future: she will arrive / she will come tomorrow morning.

If you wanted to say she is coming tomorrow morning in a more ongoing or scheduled sense, Polish might use a different structure, depending on context. But with przyjedzie, the standard interpretation is future completion: she will arrive.