Перед экзаменом я чувствую лёгкую тревогу и замечаю несколько тревожных мыслей, но дышу глубоко.

Before an exam I feel slight anxiety and notice a few anxious thoughts, but I breathe deeply.

Breakdown of Перед экзаменом я чувствую лёгкую тревогу и замечаю несколько тревожных мыслей, но дышу глубоко.

• я: I
• и: and
• перед: before
• но: but
• чувствовать: to feel
• экзамен: the exam
• несколько: a few
• дышать: to breathe
• глубоко: deeply
• замечать: to notice
• мысль: the thought
• лёгкий: slight
• тревога: the anxiety
• тревожный: anxious

Questions & Answers about Перед экзаменом я чувствую лёгкую тревогу и замечаю несколько тревожных мыслей, но дышу глубоко.

Why is экзаменом in the instrumental case after перед and not перед экзамен?

In Russian, the preposition перед (“in front of; before (in time)”) always takes the instrumental case.

So you must say:

• перед экзаменом – before the exam
• перед встречей – before the meeting
• перед сном – before sleep

The noun экзамен declines like this (singular):

• Nom.: экзамен
• Gen.: экзамена
• Dat.: экзамену
• Acc.: экзамен
• Instr.: экзаменом ← used after перед
• Prep.: об экзамене

Using nominative перед экзамен would be ungrammatical; the preposition fixes the case choice here.

Why is лёгкую тревогу in the accusative case, and how does the adjective agree with the noun?

The verb чувствовать (to feel) takes a direct object in the accusative case.
The thing you feel is:

• чувствовать что? – лёгкую тревогу

Тревога is a feminine noun (ending in -а in nominative singular), so its accusative singular is:

• Nom. sg.: тревога
• Acc. sg.: тревогу

The adjective лёгкий (light, slight) must agree with тревога in:

• gender: feminine
• number: singular
• case: accusative

So the full paradigm (feminine singular) is:

• Nom.: лёгкая тревога
• Acc.: лёгкую тревогу

That’s why you get лёгкую тревогу as the object of чувствую.

Why do we say несколько тревожных мыслей with genitive plural, not nominative plural тревожные мысли?

The word несколько (several, a few) requires the genitive plural of the noun:

• несколько чего? – несколько тревожных мыслей

Pattern:

• несколько книг (a few books)
• несколько друзей (a few friends)
• несколько важных вопросов (a few important questions)

So:

• Nominative plural: тревожные мысли (anxious/worrying thoughts – as a subject)
• Genitive plural: тревожных мыслей (of anxious/worrying thoughts – after несколько)

The adjective тревожный must also be in genitive plural to agree:

• Gen. pl.: тревожных
• Gen. pl. of мысль: мыслей

Therefore: несколько тревожных мыслей is grammatically required after несколько.

Why does мысль become мыслей in the genitive plural? Is this an irregular form?

Мысль (thought) is a feminine noun ending in a soft sign -ь, and many such nouns form the genitive plural with -ей:

• мысль → gen. pl. мыслей
• дверь → дверей
• ночь → ночей

So:

• Nom. sg.: мысль
• Gen. pl.: мыслей

This is not truly “irregular”; it’s a common pattern for feminine soft-sign nouns. It just doesn’t look transparent to learners because the stem changes in spelling and sound a little: мысль → мыслей (consonant cluster сл + ending -ей).

What is the difference between замечаю and замечу / заметил? Why is imperfective used here?

Russian has aspect: imperfective vs perfective.

• замечать – imperfective (to notice, to be noticing, to keep noticing)
  
  • я замечаю – I notice / I am noticing / I tend to notice
• заметить – perfective (to notice once, to manage to notice)
  
  • я замечу – I will notice (single event)
  • я заметил – I noticed (completed event in the past)

In the sentence, the speaker describes what typically happens or what they experience in that situation (before exams):

• я чувствую… и замечаю… → an ongoing, characteristic state/process

So the imperfective present замечаю is natural: it describes a general, repeated or extended process, not one single completed act.
If you used perfective замечу / заметил, it would sound like focusing on one particular act of noticing, not on the overall state.

Why is it дышу глубоко and not something like я дыхаю глубоко or дышаю?

The infinitive is дышать (to breathe), and its conjugation is irregular in 1st person singular:

• я дышу
• ты дышишь
• он/она дышит
• мы дышим
• вы дышите
• они дышат

There is no form дыхаю or дышаю for this verb in standard Russian; those would be incorrect.

So:

• я дышу глубоко – I breathe deeply

Глубоко is an adverb meaning deeply, so it modifies the verb дышу (how do I breathe?).

Could we say я чувствую себя тревожным instead of я чувствую лёгкую тревогу? What is the difference?

Both are possible, but they express your state in slightly different ways:

1. Я чувствую лёгкую тревогу.

   • Literally: I feel a slight anxiety.
   • Focuses on the feeling as a “thing” (an emotion) that appears in you.
   • Neutral, natural phrase for “I feel a bit anxious / some mild anxiety.”

2. Я чувствую себя тревожным.

   • Literally: I feel myself (being) anxious.
   • чувствовать себя + (instrumental adjective) describes how you perceive your own condition or role.
   • It sounds like a self-characterization: “I feel like I am an anxious person (right now).”

In this context (moments before an exam), я чувствую лёгкую тревогу sounds more natural and idiomatic: you’re describing a passing emotion.
Я чувствую себя тревожным is grammatically correct but has more of a “I’m in an anxious state / I perceive myself as anxious” nuance, and might sound a bit heavier or more personality-like.

What is exactly the nuance of лёгкую тревогу? Is it “a light anxiety”, “slight worry”, or something else? Are there synonyms?

Лёгкая тревога literally is “light / mild anxiety”. In natural English, it’s close to:

• a slight worry
• mild anxiety
• a bit of nervousness

It means the emotion is present but not strong; it doesn’t overwhelm you.

Common synonyms / near-synonyms in Russian:

• лёгкое волнение – slight nervousness/excitement
• лёгкое беспокойство – mild worry
• немного тревоги – a bit of anxiety
• чуть-чуть волнуюсь – I’m a little nervous

So лёгкую тревогу suggests a noticeable but manageable level of anxiety.

Why do we use a comma before но in ..., но дышу глубоко? Is the comma always required with но?

In this sentence, но connects two clauses with their own verbs:

• я чувствую лёгкую тревогу и замечаю несколько тревожных мыслей
• (я) дышу глубоко

They are independent clauses joined by a coordinating conjunction но (but). In Russian, when но connects two independent clauses, a comma is mandatory before it:

• …, но …

Examples:

• Я устал, но продолжаю работать.
• Он опоздал, но извинился.

However, if но connects two homogeneous parts inside one clause (e.g., two adjectives, two verbs with one subject and no subject ellipsis), the comma may or may not appear depending on the structure.
In the sentence you gave, the second part но дышу глубоко is clearly another clause (another predicate), so the comma is required.

Can the word order change, for example я глубоко дышу or лёгкую тревогу я чувствую? Does the meaning change?

Yes, Russian word order is relatively flexible, and all of these are possible:

• Я дышу глубоко. (neutral: I breathe deeply)
• Я глубоко дышу. (slightly emphasizes “deeply”)
• Лёгкую тревогу я чувствую. (focus on what I feel: it’s slight anxiety that I feel)
• Я чувствую лёгкую тревогу. (neutral order: subject – verb – object)

The basic meaning doesn’t change; what changes is information focus:

• Moving лёгкую тревогу to the front (Лёгкую тревогу я чувствую) can answer a question like:
  Что ты чувствуешь? – What do you feel?
  → Лёгкую тревогу я чувствую. – It’s slight anxiety that I feel.

For learners, the safest neutral word order is:

• Перед экзаменом я чувствую лёгкую тревогу и замечаю несколько тревожных мыслей, но дышу глубоко.

What is the difference between перед экзаменом and до экзамена?

Both can refer to time before the exam, but they have different nuances:

• перед экзаменом

  • literally “right before the exam / in the time immediately leading up to the exam”
  • suggests the time close to the event (e.g., the same day, moments before)
  • very natural for describing what you feel as the exam approaches

• до экзамена (до + genitive: до экзамена)

  • literally “until / before the exam (in general)”
  • can refer to any time earlier, not necessarily just right before
  • often used for deadlines or longer periods:
    
    • до экзамена осталось два дня – There are two days left until the exam.
    • мне нужно подготовиться до экзамена – I need to prepare before the exam.

In your sentence, перед экзаменом is better because you describe your state just before taking the exam.

How is лёгкую тревогу pronounced, especially the ё and the ending -ую?

Approximate pronunciation (IPA): [ˈlʲɵk.kʊ.jʊ trʲɪˈvo.ɡʊ]

Breakdown:

• лёгкую
  
  • лёг-: ё is always stressed and pronounced like “yo” ([ɵ] here, closer to “yoh” than plain “o”), the consonant г is softish before кк cluster in fast speech; double кк is often simplified when spoken quickly.
  • -кую: -кую → [kʊ.jʊ]; у is like “oo” in “book” (short), and ю in unstressed position often sounds like “yu” but weaker.

So it roughly sounds like: LYOHK-koo-yu (with stress on лёг-).

• тревогу
  
  • тре-: е here is like “ye” → [trʲɪ-] (soft т
    • “i/ye” sound)
  • -во-: во like “vo” in “vote” but shorter
  • -гу: гу like “goo” in “good” (but shorter)

Stress:

• лЁгкую – stress on лёг-
• тревОгу – stress on -во-

Rough English-friendly representation: LYOHK-koo-yu treh-VOH-goo.