Learn Hardcore Russian: Мне легко говорить по-русски с другом. - It is easy for me to speak Russian with a friend.

Russian often uses the dative case to express the person who experiences a feeling, state, or possibility in so‑called impersonal constructions:

Мне холодно. – It’s cold for me / I’m cold.
Тебе интересно. – It’s interesting for you.
Ему легко говорить. – It’s easy for him to speak.

So Мне легко… literally is “To me [it is] easy…”.
Using я (Я легко говорить…) would be ungrammatical here.

Who is the subject of this sentence? There is no я and no clear subject.

Grammatically, this is an impersonal sentence — it doesn’t have a subject in the usual sense.

Мне – dative “experiencer” (the person for whom it is easy)
легко – predicative word meaning “it is easy”
говорить – infinitive “to speak”
по-русски с другом – adverbial complements (how? with whom?)

Russian often uses such subjectless structures, especially with feelings, states, and evaluations:

Мне грустно. – I am sad.
Тебе трудно работать. – It’s hard for you to work.
Ему скучно одному. – He is bored alone.

So semantically you are the one speaking, but grammatically the sentence has no explicit subject.

Why is it говорить (infinitive) and not something like говорю?

After words like легко, трудно, приятно, интересно, нельзя, Russian usually uses the infinitive to express “doing something is easy/hard/pleasant/etc.”

Мне легко говорить. – It is easy for me to speak.
Тебе трудно читать по-русски. – It is hard for you to read in Russian.
Ей приятно работать здесь. – It is pleasant for her to work here.

If you said Я легко говорю по-русски, you’d be saying something different (see further below). The pattern кому + легко/трудно + infinitive is standard Russian.

What exactly is легко? Is it an adjective or an adverb? Why doesn’t it agree with anything?

In this usage легко is a predicative word (often called a “category of state” in Russian grammar). It functions similarly to an adverb meaning “it is easy”.

It does not change form for gender, number, or case.
It typically appears in impersonal constructions:
- Мне легко. – It’s easy for me.
- Ему трудно. – It’s hard for him.
- Им интересно. – It’s interesting for them.

It’s historically related to the adjective лёгкий (“light, easy”), but in modern usage here it behaves like a separate, invariable word.

So you do not say мне лёгкий говорить, only мне легко говорить.

What is the difference between Мне легко говорить по-русски and Я легко говорю по-русски?

They are both grammatical but mean different things:

Мне легко говорить по-русски.
Focus: the level of difficulty for you.
→ Speaking Russian is easy for me. (no stress, no effort)
Я легко говорю по-русски.
Focus: how you perform the action (manner).
→ I speak Russian easily / without difficulty / without effort.
This can sound like you’re boasting about your ability, or simply describing the manner of your speech.

For everyday “It’s easy for me to speak Russian”, the natural sentence is Мне легко говорить по-русски.

Why is it по-русски and not на русском or по-русскому?

With languages, Russian normally uses:

по-русски – an adverb meaning “in Russian / in a Russian way”
на русском (языке) – “in the Russian language”

In the context of speaking a language, the most common options are:

говорить по-русски
говорить на русском (языке)

Both mean “to speak Russian”. по-русски is slightly more colloquial and very common in speech.

по-русскому is wrong here; по + dative is used with school subjects (e.g. по русскому языку = “in Russian (class)”).

So:

Мне легко говорить по-русски. – normal, very natural.
Мне легко говорить на русском. – also correct, a bit more formal or neutral.

Why is it с другом and not с друг?

The preposition с (“with”) in the meaning “together with someone” requires the instrumental case.

друг – nominative (dictionary form)
другом – instrumental singular

So you must say:

с другом – with (a) friend
с подругой – with (a) female friend
с братом – with (my) brother
с учителем – with (my) teacher

Using с друг would be ungrammatical because друг is nominative, not instrumental.

Could it be со другом instead of с другом?

No. The correct form is с другом.

Russian sometimes uses со instead of с to make pronunciation easier, usually before certain consonant clusters:

со мной, со мной (s + m → hard to pronounce as смной)
со столом (optional; many people still say с столом in casual speech)
со вчерашнего дня

But before д, с другом is easy to pronounce, so the standard form is с другом, not со другом.

Can I change the word order, for example: С другом мне легко говорить по-русски?

Yes. Russian word order is relatively flexible; it mainly affects emphasis and style, not grammar.

Some possible variants:

Мне легко говорить по-русски с другом. – neutral, common.
Мне легко с другом говорить по-русски. – slight emphasis on “with a friend”.
С другом мне легко говорить по-русски. – strong emphasis on “With a friend, it’s easy for me…”.
Говорить по-русски с другом мне легко. – emphasis on “easy”; sounds a bit more bookish or expressive.

All are correct; the basic structure and cases stay the same.

Why is it говорить, not сказать? What would Мне легко сказать по-русски с другом mean?

говорить and сказать are different aspects and meanings:

говорить – imperfective, “to speak, to be speaking” (a process, ongoing action).
сказать – perfective, “to say (once), to have said” (a single, completed act).

In this sentence you mean the general ability / process of speaking Russian, so you use говорить:

Мне легко говорить по-русски. – It’s easy for me to speak Russian (in general / as an activity).

Мне легко сказать по-русски… would usually need a specific object:

Мне легко сказать это по-русски. – It’s easy for me to say this in Russian.

Your exact phrase “Мне легко сказать по-русски с другом” sounds unnatural and incomplete. For talking comfortably in Russian with someone, always use говорить / разговаривать, not сказать.

Can I say Мне легко разговаривать по-русски с другом instead? What’s the nuance?

Yes, that is also correct. The nuance:

говорить – “to speak”, more general; covers speaking, talking, speaking a language.
разговаривать – “to converse, to chat, to talk with someone” (two-sided exchange).

So:

Мне легко говорить по-русски с другом.
→ It’s easy for me to speak Russian with my friend. (general)
Мне легко разговаривать по-русски с другом.
→ It’s easy for me to have conversations / chat in Russian with my friend.

Both are fine; разговаривать slightly emphasizes the interactive conversation.

Why is there no word for “is” (like есть) in this sentence?

In the present tense, Russian usually omits the verb “to be” (быть / есть) in simple “X is Y” sentences:

Он студент. – He is a student.
Она дома. – She is at home.
Мне легко. – It is easy for me.

So your sentence is understood as:

Мне (есть) легко говорить по-русски с другом.
→ “For me, it is easy to speak Russian with a friend.”

The verb есть is normally not spoken in such present‑tense constructions; it appears in the past and future (был, будет, etc.) or for special emphasis.