Во время сессии я пью больше кофе и реже встречаюсь с друзьями.

Во время means during or literally in the time of. After во время, Russian uses the genitive case, so сессия becomes сессии.

• сессия = session / exam period
• во время сессии = during the exam period

This is a fixed and very common structure:

• во время урока = during the lesson
• во время каникул = during the holidays
• во время встречи = during the meeting

Not exactly in the everyday English sense. In this sentence, сессия usually means the exam period at a university or college. So a native Russian speaker would most likely understand this as:

• during exams
• during the exam session
• during finals/exam period

This is a very common student-life word in Russian.

The verb is пить = to drink, and its present-tense forms are somewhat irregular.

Conjugation:

• я пью = I drink
• ты пьёшь
• он / она пьёт
• мы пьём
• вы пьёте
• они пьют

So я пью is simply the correct 1st person singular form.

Also note the pronunciation: the ь softens the sound, and пью is pronounced roughly like pyu.

Больше is the normal word for more when talking about quantity.

• я пью больше кофе = I drink more coffee

Более is usually more formal and is more often used in expressions like more + adjective/adverb:

• более интересный = more interesting
• более точно = more precisely

So with nouns and amounts, больше is the natural choice.

Because the sentence does not explicitly say more than before or more than usual. Russian often leaves that comparison understood from context.

So:

• я пью больше кофе = I drink more coffee

This naturally implies more than usual / more than at other times.

If you want to state the comparison explicitly, you can add it:

• я пью больше кофе, чем обычно = I drink more coffee than usual
• я пью больше кофе, чем раньше = I drink more coffee than before

Because кофе is generally an indeclinable noun in standard Russian, so it often keeps the same form in different cases.

Here it appears after больше, and the form is still кофе.

A useful thing to know: traditionally, кофе is treated as masculine in standard Russian:

• горячий кофе

But in modern spoken Russian, some people also use it as neuter. For learners, it is safest to remember the standard literary norm:

• кофе = usually masculine, and its form does not change

Реже means more rarely, less often, or simply not as often.

It is the comparative form related to:

• редко = rarely
• реже = more rarely / less often

So:

• я реже встречаюсь с друзьями = I meet up with friends less often

This is a very natural way in Russian to talk about frequency.

Because when talking about how often something happens, Russian usually uses comparative adverbs of frequency, not a direct equivalent of English less.

Compare:

• часто = often
• реже = less often / more rarely

So in Russian, реже встречаюсь sounds natural, while trying to translate English word-for-word with меньше would not work here.

Use:

• меньше for quantity/amount: я пью меньше кофе = I drink less coffee
• реже for frequency: я реже встречаюсь с друзьями = I meet friends less often

Both are possible, but they mean slightly different things.

1. встречаться с кем-то = to meet with someone / to get together with someone

   • я встречаюсь с друзьями = I meet up with friends

2. встречать / встретить кого-то = to meet / encounter / greet someone

   • я встречаю друзей can mean I meet my friends in the sense of encountering them or going to greet them

In your sentence, the idea is about socializing less often, so встречаюсь с друзьями is the natural choice.

Because the verb встречаться normally takes с + instrumental.

So:

• с другом = with a friend
• с друзьями = with friends

This is a very common pattern in Russian:

• говорить с другом = to talk with a friend
• встречаться с друзьями = to meet up with friends
• гулять с семьёй = to walk/spend time with family

The base noun is:

• друзья = friends

But after с in this structure, it becomes:

• с друзьями

The -сь is the reflexive ending, a variant of -ся. It is attached to verbs and can change the meaning in different ways.

Here:

• встречать = to meet, to greet
• встречаться = to meet each other / to meet up / to be seeing each other

In this sentence, встречаюсь means I meet up or I get together.

The short version:

• -ся / -сь often creates a reflexive or reciprocal meaning
• after a vowel, it is often written as -сь
• after a consonant, it is usually -ся

So:

• встречаюсь
• встречается

Because Russian uses the present tense for repeated, habitual, or general actions happening in a current time frame.

So:

• Во время сессии я пью больше кофе = During exam period, I drink more coffee
• я реже встречаюсь с друзьями = I meet with friends less often

This does not mean only right this second. It can describe a regular pattern.

English does the same:

• During finals, I drink more coffee
• I see my friends less often

Because the sentence describes habitual/repeated behavior, not one completed action.

• пить (imperfective) = to drink, in general / repeatedly
• встречаться (imperfective) = to meet up, repeatedly / as a habit

During an exam period, the speaker is describing a pattern:

• they drink more coffee
• they meet friends less often

If Russian used perfective verbs here, it would sound like specific completed events, which is not the point.

Yes, often you can.

Russian frequently drops subject pronouns when the verb ending already makes the subject clear.

So both are possible:

• Во время сессии я пью больше кофе и реже встречаюсь с друзьями.
• Во время сессии пью больше кофе и реже встречаюсь с друзьями.

Including я is fine too. It can add a little emphasis or just make the sentence feel more explicit.

No, Russian word order is fairly flexible, though some versions sound more neutral than others.

The given sentence is natural and neutral:

• Во время сессии я пью больше кофе и реже встречаюсь с друзьями.

You could also say:

• Я во время сессии пью больше кофе и реже встречаюсь с друзьями.
• Больше кофе я пью во время сессии и реже встречаюсь с друзьями.

But changing the order changes the emphasis. The original version is probably the best one for a learner to use in normal speech.

Because и joins two parts with the same subject:

• я пью больше кофе
• (я) реже встречаюсь с друзьями

In Russian, when two predicates share the same subject and are connected by и, you normally do not put a comma.

So:

• я пью больше кофе и реже встречаюсь с друзьями

No comma is needed.

Yes. Very often it means exactly that: I socialize with my friends less often.

Russian встречаться с друзьями can mean physically meeting them, but in context it often has the broader sense of:

• getting together
• hanging out
• seeing each other socially

So the phrase sounds very natural in the context of being busy during exams.