Learn Hardcore Russian: Это не значит, что урок будет лёгким. - This does not mean that the lesson will be easy.

Это не значит, что… = It doesn’t mean that…
Without это (just Не значит, что…) it sounds incomplete or too colloquial, as if something is missing before the verb.

You can drop это in very casual or very compressed speech if the subject is crystal clear from context, but the neutral, correct form for a full sentence is Это не значит, что….

What form is значит? What is the infinitive of this verb?

значит is:

tense: present
person: 3rd person
number: singular
verb: значить (infinitive)

So it literally means “(it) means”.

это значит = this/that means
это не значит = this/that does not mean

Infinitive: значить = to mean.

Is значит the same as означает? Could I say Это не означает, что… instead?

They are very close, and in this sentence they’re practically interchangeable.

значит – more common, short, very neutral.
означает – from означать, a bit more “formal” or “bookish,” often used in definitions, explanations, official style.

Это не значит, что урок будет лёгким.
Это не означает, что урок будет лёгким.

Both are correct and natural. The difference in tone is small; значит is slightly more everyday.

Why is не placed before значит and not somewhere else?

In Russian, the basic negation pattern is:

не + conjugated verb

So:

значит → не значит = doesn’t mean

You normally can’t move не far away from the verb like in English. You don’t say:

✗ это значит не, что…

The natural position is exactly не значит.

What does что mean here? Is it the same что as in what?

что has several functions in Russian.

Here it is a subordinating conjunction meaning “that”, introducing a clause:

…что урок будет лёгким. = …that the lesson will be easy.

So it’s the “that” in “It doesn’t mean that the lesson will be easy.”

It is not the interrogative что? (what?) here, even though they look the same in writing.

Can Russian omit что like English sometimes omits “that”? (e.g. “It doesn’t mean (that) the lesson will be easy.”)

No, not in this kind of sentence. In Russian, the conjunction что is usually required to introduce such a subordinate clause.

English: It doesn’t mean (that) the lesson will be easy. – “that” is optional.
Russian: Это не значит, что урок будет лёгким. – что is needed.

If you remove что, the sentence becomes wrong or at least very unnatural:

✗ Это не значит, урок будет лёгким. – incorrect.

Why is there a comma before что?

Russian almost always puts a comma before что when it introduces a subordinate clause (a “that”-clause).

Structure:

Main clause: Это не значит
Subordinate clause: что урок будет лёгким

In Russian punctuation, you separate those with a comma:

Это не значит, что урок будет лёгким.

Why is урок in the nominative case? Shouldn’t there be some special case after что or значит?

Within the subordinate clause что урок будет лёгким, you have a normal subject–predicate structure:

subject: урок (the lesson) → nominative singular masculine
predicate: будет лёгким (will be easy)

The conjunction что does not force a special case. It just introduces a full clause with its own grammar. Inside that clause, урок is simply the subject, so nominative is required.

What form is будет? How does it make the future tense here?

будет is:

tense: future
person: 3rd
number: singular
verb: быть (to be)

Pattern: быть (future) + predicate = will be.

So:

урок будет лёгким = the lesson will be easy

This is the normal way to form the future of “to be” plus an adjective or noun.

Why is it лёгким and not лёгкий?

лёгким is:

masculine
singular
instrumental case
short-form adjectival predicate

In Russian, after быть (and some other verbs), a predicate noun or adjective can appear in the instrumental to describe what something is / will be / becomes, especially in a slightly more “descriptive” or “resultative” tone.

Compare:

Урок будет лёгкий.
- nominative predicate adjective
- very neutral statement: The lesson will be easy.
Урок будет лёгким.
- instrumental predicate adjective
- often feels a bit more descriptive or contrastive: The lesson will turn out / will be of the “easy” kind.

In everyday speech, both are grammatical and often interchangeable. Many speakers don’t feel a strong difference here.

So is there any meaning difference between урок будет лёгкий and урок будет лёгким?

Both can mean “the lesson will be easy,” and both are correct.

Subtle tendencies (not strict rules):

урок будет лёгкий – straightforward characterisation, more plain, just a fact.
урок будет лёгким – can sound a bit more like “the lesson will turn out easy / will be of an easy nature,” sometimes slightly more stylistic or contrastive (e.g. opposed to being difficult).

In many real-life contexts, Russians use them almost interchangeably, and the difference is small.

Why does лёгким end with -им? How does it agree with урок?

Agreement:

урок – masculine, singular
Adjective лёгкий in instrumental masculine singular is лёгким.

Pattern (masculine singular instrumental of adjectives like новый, лёгкий):

новый → новым
лёгкий → лёгким

So лёгким matches урок in gender (masculine) and number (singular), and takes the instrumental ending -им because of its role as a predicate with будет.

Is значит here the same as the conversational “значит…” people use like “so, then…”?

It’s the same word, but used in a different way.

In your sentence:
- Это не значит, что… = It doesn’t mean that…
- Here значит is a normal verb (means).
In conversation:
- Значит, ты уже уехал? – So, you’ve already left?
- Here значит functions more like a discourse marker, similar to “so / that means / well then”.

Grammatically they come from the same verb значить, but in everyday speech, the discourse-marker use feels more like a fixed filler word.