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Learn Hardcore Czech: On je můj bratr. - He is my brother.

Hardcore Czech
/Lesson 4
/On je můj bratr.

On je můj bratr.

On je můj bratr.

He is my brother.

Breakdown of On je můj bratr.

Questions & Answers about On je můj bratr.

Do I really need to say On? Can I just say Je můj bratr?

In Czech, the subject pronoun (on, ona, oni, etc.) is often dropped because the verb form already shows the person and number.

So:

On je můj bratr. = He is my brother. (neutral, or with light emphasis on “he”)
Je můj bratr. = He is my brother. (grammatically correct, often sounds a bit more contextual, like answering “Who is he?”)

You usually:

Keep on when you want to emphasize he (as opposed to someone else), or at the start of a new topic.
Drop it in flowing conversation when it’s clear who you’re talking about.

Both forms are grammatically fine.

What is the difference between On je můj bratr and To je můj bratr?

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Both can translate as “He is my brother.”, but they are used a bit differently:

On je můj bratr.
Literally He is my brother.
Used more when “he” is already clear from context (you’re already talking about him) and you’re making a statement about him.
To je můj bratr.
Literally That is my brother.
Very common when:
- You are introducing someone: To je můj bratr. (This is my brother.)
- You point at someone or something: Kdo je ten muž? – To je můj bratr.

In everyday speech, To je můj bratr. is usually the default when you’re identifying someone.

Why is it můj bratr and not moje bratr or mého bratra?

Můj is a possessive pronoun meaning “my” and it must agree with the noun in gender, number, and case.

bratr (brother) is masculine singular, nominative case.
The correct form for “my” with a masculine singular noun in nominative is můj.

So:

můj bratr – my brother (masculine, subject or predicate)
moje sestra – my sister (feminine)
moje auto – my car (neuter)

Mého bratra is a different case (genitive/accusative), used for example:

Vidím mého bratra. – I see my brother.
Nemám bratra. – I don’t have a brother.

In On je můj bratr, both on and bratr are in nominative, so můj is the right form.

Why isn’t there an article like “a” or “the” before bratr?

Czech does not have articles (no equivalent of “a/an” or “the”). The noun bratr on its own can mean:

a brother
the brother
just brother in general

The exact meaning is understood from context. So:

On je můj bratr. can be understood as:
- He is my brother.
- He’s the brother of mine (in a specific context)

You never add anything like an article in front of bratr. Just bratr or můj bratr is correct.

Why is it bratr and not bratra or bratrem here?

Czech uses cases. The form of the noun changes depending on its role in the sentence.

In On je můj bratr.:

On is the subject (nominative).
bratr is the predicate noun (= what he is), which also takes nominative in this structure.

So the nominative form is bratr.

Other forms of bratr (just for comparison):

bratra – accusative / genitive (e.g. Vidím bratra. – I see my brother.)
bratrem – instrumental (e.g. Jdu s bratrem. – I’m going with my brother.)

In “He is my brother”, we use nominative: bratr.

Can I change the word order, like Můj bratr je on?

Czech word order is more flexible than English, but not every possible order sounds natural.

On je můj bratr. – completely natural.
Můj bratr je on. – grammatical, but sounds unusual; it heavily emphasizes “he (and not someone else) is my brother,” and is rarely used in speaking.
Je můj bratr on. or Můj je on bratr. – effectively wrong / very unnatural.

As a learner, treat On je můj bratr. and To je můj bratr. as the default natural patterns. Avoid trying to “shuffle” the words too freely at first.

What exactly does je mean, and what are the other forms of this verb?

Je is the 3rd person singular present form of the verb být – “to be”.

Basic present tense forms of být:

já jsem – I am
ty jsi – you are (singular, informal)
on / ona / ono je – he / she / it is
my jsme – we are
vy jste – you are (plural OR polite singular)
oni jsou – they are

So On je = “He is”.

Note: je can also be a pronoun meaning “them” in other contexts, but in On je můj bratr, it is the verb “is”.

How do I say “He is not my brother” in Czech?

You don’t make the verb negative with a separate word like “not”. Instead, Czech uses a negative form of the verb.

On je můj bratr. – He is my brother.
On není můj bratr. – He is not my brother.

The negative of je is není. You don’t say “je ne” in Czech.

How should I pronounce On je můj bratr?

Approximate pronunciation (using English-like hints):

On – like “on” in English, but with a shorter, cleaner vowel.
je – sounds like “yeh”.
můj –
- m as in man
- ů is a long “oo” sound (like in “food”)
- j is like English “y” in “yes”
  So můj ≈ “mooy”.
bratr –
- b – as in bed
- r – rolled or tapped (like Spanish r)
- a – like “u” in cup but a bit more open, or “a” in “father” but shorter
- tr – like “tr” in tree, but the r is rolled
  There are two r sounds: b-ra-tr.

Stress in Czech is almost always on the first syllable of each word: ON je MŮJ BRATR (though “je” is weak and often less stressed).

Is bratr the normal word in everyday speech, or is there a more casual word for “brother”?

Bratr is the standard, neutral word for “brother”. It’s fine in both formal and informal contexts.

Colloquial alternatives:

brácha – very common informal/slang, like “bro” or “brother” casually.
- To je můj brácha. – This is my (brother / bro).

As a learner:

Use bratr in all situations;
Learn brácha as a friendly, informal option you’ll hear from native speakers.

How would the sentence change if I were talking about my sister instead of my brother?

You’d need to change both the noun and the possessive to match the feminine gender:

On je můj bratr. – He is my brother.
Ona je moje sestra. – She is my sister.

Changes:

On → Ona (he → she).
můj → moje (my, agreeing with a feminine noun).
bratr → sestra (sister).

Similarly, for introducing:

To je moje sestra. – This is my sister.

Can I replace On with a name, like “Petr je můj bratr”?

Yes. Any noun or name can be the subject instead of on:

On je můj bratr. – He is my brother.
Petr je můj bratr. – Petr is my brother.

Using the name often sounds more natural if you’re specifying who you’re talking about. You would usually only use On when:

The person has already been introduced, or
You want to emphasize he (not someone else).

Why is it můj bratr, but moje sestra and moje auto? How do I know which form of “my” to use?

The possessive “my” in Czech has several forms that agree with the gender and number of the noun:

Singular:

můj – with masculine nouns:
- můj bratr – my brother
moje (also written má, more formal/poetic) – with feminine nouns:
- moje sestra – my sister
moje – with neuter nouns:
- moje auto – my car

Plural (for “my …s”):

moji / mí – masculine animate plural:
- moji bratři – my brothers
moje – feminine plural and neuter plural:
- moje sestry – my sisters
- moje auta – my cars

So in On je můj bratr, you use můj because bratr is masculine singular.

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