Babcia przyjedzie pociągiem w niedzielę rano.

Przyjedzie is the 3rd person singular future form of the perfective verb przyjechać, meaning to arrive / come by vehicle.

So:

• przyjechać = to arrive by transport, to come by car/train/bus, etc.
• przyjedzie = he/she/it will arrive

Because babcia is grammatically she, przyjedzie means grandma will arrive.

A useful comparison:

• jedzie = is going / is riding / is traveling (imperfective, present)
• przyjeżdża = arrives / is arriving regularly (imperfective)
• przyjedzie = will arrive (perfective, one completed future event)

So this sentence talks about one future arrival, which is why przyjedzie fits.

This is a very common question.

• jechać means to go / travel / ride by some means of transport
• przyjechać means to arrive / come by transport, with the prefix przy- adding the idea of arrival toward a destination

Compare:

• Babcia jedzie. = Grandma is traveling / going
• Babcia przyjedzie. = Grandma will arrive

So przyjedzie focuses on the endpoint of the journey, not the journey itself.

Pociągiem is the instrumental singular form of pociąg (train).

Polish often uses the instrumental case to express means of transport, especially when English uses by:

• samochodem = by car
• autobusem = by bus
• pociągiem = by train
• taksówką = by taxi

So:

• pociąg = train
• pociągiem = by train

This is why the sentence does not need a separate word for by.

Very often, yes, when you mean by means of a vehicle.

Examples:

• Jadę autobusem. = I’m going by bus.
• Przyjechała samochodem. = She arrived by car.
• Polecimy samolotem. = We’ll go by plane.

But Polish can also use prepositions in other transport-related expressions, for example:

• w pociągu = on the train
• na autobus = for the bus / onto the bus, depending on context

So for means of transport, instrumental is very common:

• pociągiem = by train

Because after w meaning on with days of the week, Polish uses the accusative.

So:

• niedziela = Sunday
• w niedzielę = on Sunday

Other examples:

• w sobotę = on Saturday
• w środę = on Wednesday

This is something learners usually just have to get used to as a pattern:

• w + accusative for on a certain day

Because rano is already an adverb meaning in the morning / morning.

So:

• w niedzielę rano = on Sunday morning

You do not say w rano here.

Other time adverbs work similarly:

• wieczorem = in the evening
• nocą = at night / during the night
• jutro rano = tomorrow morning

So rano functions naturally by itself as a time expression.

Treat it as one combined time phrase:

• w niedzielę = on Sunday
• rano = in the morning

Together:

• w niedzielę rano = on Sunday morning

Polish often stacks time expressions this way without needing extra linking words.

Yes. Polish word order is more flexible than English because case endings help show what each word is doing.

The neutral version here is:

• Babcia przyjedzie pociągiem w niedzielę rano.

But you could also say:

• Babcia w niedzielę rano przyjedzie pociągiem.
• W niedzielę rano babcia przyjedzie pociągiem.
• Pociągiem babcia przyjedzie w niedzielę rano.

These all mean roughly the same thing, but the emphasis changes:

• sentence-initial W niedzielę rano... emphasizes the time
• sentence-initial Pociągiem... emphasizes the means of transport

So the original sentence is natural and neutral, but not the only possible order.

Because Polish has no articles like a or the.

So:

• babcia can mean grandma, a grandma, or the grandma, depending on context
• pociąg / pociągiem can mean train / a train / the train, depending on context

English requires articles, but Polish does not.

Usually babcia is the everyday, affectionate word grandma rather than the more formal grandmother.

It is a normal, very common word in Polish.

In this sentence, Babcia is capitalized because it is the first word of the sentence. In the middle of a sentence, it would normally be written babcia, unless someone is using it like a name in direct address.

Because Polish usually does not need subject pronouns when the verb ending already shows the person and number.

Here, przyjedzie already tells us it is he/she/it will arrive, and the noun Babcia makes it clear who that is.

So Polish normally says:

• Babcia przyjedzie.

not:

• Babcia ona przyjedzie.

Using ona would usually sound unnecessary unless you want special emphasis or contrast.

Yes. In natural English, przyjedzie can often be translated as either:

• will arrive by train
• will come by train

The Polish verb specifically suggests movement by vehicle and arrival, but in English the best translation depends on context.

So both are reasonable, even though the Polish verb has a slightly more specific sense than plain English come.

A rough pronunciation is:

pshih-YEH-jeh

A few helpful points:

• przy- sounds roughly like pshi or pshih
• je sounds like ye
• dzie sounds like a soft je sound, something like jeh

The whole word is pronounced smoothly as three parts:

• przy
• je
• dzie

If you want a more detailed approximation: pshih-YED-zyeh can also help some learners, though no English spelling matches it perfectly.

It describes a one-time completed future event: grandma’s arrival.

That is one reason the perfective verb przyjedzie is used.

If you wanted to talk about repeated arrivals or a habitual action, Polish would usually use an imperfective verb instead, for example with a different context:

• Babcia przyjeżdża pociągiem w niedzielę rano.
  = Grandma comes by train on Sunday morning / Grandma is arriving by train on Sunday morning, depending on context

But in your original sentence, the meaning is clearly one future arrival.