Лютий холодніший, ніж березень.

In Ukrainian, the verb to be is usually left out in the present tense.

So:

• Лютий холодніший, ніж березень. literally looks like:
• February colder than March.

But it naturally means:

• February is colder than March.

This is completely normal in Ukrainian.

Ніж means than in comparisons.

So:

• холодніший, ніж березень = colder than March

It is used after a comparative form such as:

• більший = bigger
• менший = smaller
• кращий = better
• холодніший = colder

Холодніший is the comparative form of холодний (cold).

• холодний = cold
• холодніший = colder

It agrees with лютий because лютий is masculine singular here.

So the form is masculine singular nominative:

• лютий холодніший = February is colder

If the noun were feminine or plural, the adjective form would change to match.

Both are month names, and here they are being compared directly:

• Лютий = February
• березень = March

In this sentence, they appear in the nominative singular form.

That is normal with this kind of comparison:

• Лютий холодніший, ніж березень.

A learner may expect a different case after than, but with ніж, Ukrainian often keeps the noun in a direct comparison form like this.

Yes. лютий can also be an adjective meaning fierce, severe, or ferocious.

But in this sentence, Лютий means February.

This is very common in Ukrainian: some month names look like ordinary words. Context tells you which meaning is intended.

For example:

• лютий мороз = severe frost
• лютий = February

It is capitalized here only because it is the first word of the sentence.

In Ukrainian, month names are normally written with a lowercase letter, unlike in English.

So inside a sentence you would write:

• У лютому холодно. = It is cold in February.

not:

• У Лютому холодно.

Yes. Ukrainian also commonly uses:

• за
• від

So these are also possible:

• Лютий холодніший за березень.
• Лютий холодніший від березня.

These all mean the same thing: February is colder than March.

The case changes depending on the word used:

• ніж березень
• за березень
• від березня

So it is worth learning each pattern separately.

Because this sentence uses ніж, not від.

Compare:

• Лютий холодніший, ніж березень.
• Лютий холодніший від березня.

After від, you use the genitive:

• березня

But in this sentence, with ніж, you get:

• березень

So the form depends on the comparison word being used.

The word order is very straightforward:

• Лютий = the thing being talked about
• холодніший = the comparative adjective
• ніж березень = the comparison

So the pattern is:

• X + comparative adjective + ніж + Y

This is a very common structure in Ukrainian.

A helpful approximation is:

• Лютий — LYU-tyy
• холодніший — kho-lo-DNEE-shyy
• ніж — neezh
• березень — be-RE-zenʹ

Approximate stress:

• Лю́тий
• холодні́ший
• ні́ж
• бере́зень

The х sound is like a throaty h/ch sound, not an English h.