Moja rodzina planuje spokojne wakacje nad morzem.

• Moja = my
• rodzina = family
• planuje = is planning / plans
• spokojne = peaceful / quiet / relaxing
• wakacje = vacation / holidays
• nad morzem = by the sea / at the seaside

So the whole sentence means something like My family is planning a peaceful vacation by the sea.

Because rodzina is a feminine noun in Polish, and the possessive adjective my must agree with it in gender, number, and case.

So:

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

Since rodzina is feminine, we say moja rodzina.

Because adjectives in Polish must agree with the noun they describe.

Here, wakacje is:

• plural
• grammatically treated as non-masculine personal plural

So the adjective takes the matching plural form:

• spokojny = peaceful, quiet
• spokojne = peaceful (plural, non-masculine-personal)

That is why we say spokojne wakacje.

Wakacje is grammatically plural in Polish.

It works like words such as holidays in English. Even when English might say a vacation, Polish often uses the plural wakacje.

So:

• wakacje = vacation / holidays
• you normally do not use it as a singular noun in this meaning

That is why the adjective is also plural: spokojne wakacje.

Because after nad, Polish uses different cases depending on meaning:

• nad + accusative = movement to a place
• nad + instrumental = location at / by a place

In this sentence, the idea is location: by the sea, not motion toward it.

So:

• morze = sea
• morzem = instrumental form

Therefore:

• nad morzem = by the sea / at the seaside
• nad morze = to the seaside / to the sea

Morzem is the instrumental singular form of morze.

The noun forms are:

• morze = nominative / accusative singular
• morza = genitive singular
• morzem = instrumental singular

Because nad here expresses location, it requires the instrumental:

• nad morzem = by the sea

Because rodzina means family, and in Polish it is a singular collective noun, just as in English.

So even though a family contains many people, the word itself is singular:

• rodzina planuje = the family is planning

That is why the verb is also singular:

• planuje, not planują

Because its subject is rodzina, which is singular.

Even though family refers to more than one person in real life, grammatically rodzina is singular, so the verb must also be singular:

• moja rodzina planuje = my family is planning

If the subject were truly plural, for example moi rodzice = my parents, then you would use a plural verb:

• Moi rodzice planują wakacje.

It can mean either, depending on context.

Polish present tense often covers both:

• plans
• is planning

So Moja rodzina planuje spokojne wakacje nad morzem could be understood as:

• My family plans a peaceful vacation by the sea
• My family is planning a peaceful vacation by the sea

In normal English, is planning is often the most natural translation here.

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

The neutral, natural order here is:

• Moja rodzina planuje spokojne wakacje nad morzem.

But other orders are possible for emphasis, for example:

• Spokojne wakacje nad morzem planuje moja rodzina.
• Nad morzem moja rodzina planuje spokojne wakacje.

These alternatives are grammatical, but they sound more marked or emphatic. For a learner, the original order is the safest and most natural.

A rough pronunciation guide is:

MO-ya ro-DJEE-na pla-NOO-ye spo-KOY-ne va-KA-tsye nad MO-zhem

A few useful points:

• j in Polish sounds like English y in yes
• rz often sounds like the zh sound in measure
• cz sounds like ch in chocolate
• w sounds like English v
• c sounds like ts

So:

• moja sounds like MO-ya
• rodzina sounds roughly like ro-DJEE-na
• planuje sounds roughly like pla-NOO-ye
• wakacje sounds roughly like va-KA-tsye
• morzem sounds roughly like MO-zhem

Because Polish has no articles like English a, an, and the.

So:

• spokojne wakacje can mean peaceful vacation, a peaceful vacation, or the peaceful vacation, depending on context

Polish speakers understand definiteness from context rather than from articles.

Yes, but that would be a different structure and meaning.

• nad morzem = by the sea / location
• na wakacje nad morzem = for a vacation by the sea

For example:

• Moja rodzina jedzie na wakacje nad morzem. = My family is going on vacation to the seaside.

But in your original sentence, planuje spokojne wakacje nad morzem, the phrase nad morzem directly describes the vacation as being by the sea, which is perfectly natural.

Not always exactly. Spokojny / spokojne can mean:

• peaceful
• calm
• quiet
• relaxing

So spokojne wakacje suggests a vacation that is calm, restful, and not hectic.

Depending on context, English translations could include:

• a peaceful vacation
• a quiet holiday
• a relaxing vacation

The dictionary forms are:

• moja → dictionary form usually given under mój = my
• rodzina = family
• planuje → infinitive planować = to plan
• spokojne → dictionary form spokojny = peaceful / calm
• wakacje = vacation / holidays
• morzem → dictionary form morze = sea

This is useful because in Polish, many words change form depending on case, gender, and number.