Breakdown of Мой брат читает книгу о космосе и строении вселенной.
Questions & Answers about Мой брат читает книгу о космосе и строении вселенной.
Читает is the 3rd person singular present tense of the verb читать (to read).
For читать the present tense forms are:
- я читаю – I read / am reading
- ты читаешь – you read / are reading (informal singular)
- он / она / оно читает – he / she / it reads / is reading
- мы читаем – we read / are reading
- вы читаете – you read / are reading (plural or polite)
- они читают – they read / are reading
Russian verbs in this group never add a final -ь in the 3rd person. The correct ending here is -ет, giving читает.
Книга becomes книгу because it is the direct object of the verb читает.
- The basic form (dictionary form) is книга – nominative case (subject form).
- After most action verbs, the thing that is acted on goes into the accusative case.
Declension of книга (singular):
- Nominative: книга (book – as subject)
- Accusative: книгу (book – as object)
So:
- Книга на столе. – The book is on the table. (subject → nominative)
- Он читает книгу. – He is reading a book. (object → accusative)
The preposition о (about) in Russian normally requires the prepositional case.
The noun космос (space) in the prepositional singular is:
- Nominative: космос
- Prepositional (after о): о космосе
So о космосе literally means about space. The ending -е is the usual prepositional ending for many masculine nouns.
Both о космосе and про космос can mean about space, and both are possible here.
Nuances:
- о космосе is more neutral, standard, and common in written and formal speech.
- про космос is a bit more colloquial and often feels slightly less formal.
In a sentence about a book, книгу о космосе sounds especially natural and a bit more bookish or formal, which fits well.
The word строении is the prepositional singular of the noun строение (structure, building, construction).
Singular forms of строение:
- Nominative: строение
- Genitive: строения
- Dative: строению
- Accusative: строение
- Instrumental: строением
- Prepositional: (о) строении
After о we use the prepositional: о строении – about the structure.
In this sentence, the preposition о is understood for the second part too:
- о космосе и (о) строении вселенной
So строении is also in the prepositional case.
Вселенной here is in the genitive singular of вселенная (universe).
Singular of вселенная:
- Nominative: вселенная
- Genitive: вселенной
- Dative: вселенной
- Accusative: вселенную
- Instrumental: вселенной / вселенною
- Prepositional: (о) вселенной
We use the genitive case to show possession or a part–whole relationship. Строение вселенной literally means the structure of the universe. So вселенной is genitive because it depends on строение (structure of what?).
In Russian, the simple present tense often covers both English meanings.
Мой брат читает книгу can be:
- My brother reads a book / reads books (habitually), or
- My brother is reading a book (right now).
Context usually clarifies the meaning.
If you really want to stress that it is happening right now, you might add something like:
- Сейчас мой брат читает книгу… – Right now my brother is reading a book…
Both are grammatically correct:
- о космосе и строении вселенной
- о космосе и о строении вселенной
Russian often omits the repeated preposition if it is clearly understood from the first noun.
The shorter version used in the sentence is completely natural and slightly more compact. Repeating о puts a bit more emphasis on the second item but is not required.
You can say Брат читает книгу…, but it sounds less natural in many contexts.
- Мой брат… – clearly means my brother.
- Брат… alone often sounds like:
- the brother in a very limited context, or
- a brother in some generic or cultural sense.
In everyday speech, when you talk about your own brother, you almost always include мой:
Мой брат читает книгу… – My brother is reading a book…
Russian does not have articles like English a / an / the.
Whether something is definite (the book) or indefinite (a book) is understood from context, word order, and sometimes other words.
So читает книгу can be:
- is reading a book
or - is reading the book
Similarly, строение вселенной is normally understood as the structure of the universe from common knowledge and context, without a special article word.
Russian word order is more flexible than English, but not everything sounds equally natural.
The neutral, most typical order here is:
- Мой брат читает книгу о космосе и строении вселенной.
You can move words for emphasis:
- Книгу о космосе читает мой брат. – Emphasis on the book about space.
- Мой брат книгу читает о космосе… – sounds awkward and unnatural.
Keep subject – verb – object as your default. Later, when you are more advanced, you can experiment with reordering for nuance.
The verb changes; everything else stays the same.
Present:
Мой брат читает книгу о космосе и строении вселенной.
– My brother is reading / reads a book…Past (imperfective, process or repeated action):
Мой брат читал книгу о космосе и строении вселенной.
– My brother was reading / used to read / read (over some time) a book…Future (compound, imperfective – focus on process):
Мой брат будет читать книгу о космосе и строении вселенной.
– My brother will be reading / will read (as an ongoing activity) a book…
You could also use perfective (прочитать) for completion:
Мой брат прочитал книгу… – My brother has read / finished reading the book…
Noun genders:
- брат – masculine
- книга – feminine
- космос – masculine
- строение – neuter
- вселенная – feminine
The possessive pronoun мой agrees with брат:
- masculine nominative singular: мой брат
- feminine nominative singular would be моя сестра (my sister)
- neuter nominative singular: моё строение
- plural: мои братья (my brothers)
So мой брат is masculine singular, nominative case, matching the subject брат.