Чай з медом смачніший, ніж чай без цукру.

In Ukrainian, the present-tense form of to be is usually omitted in simple sentences like this.

So:

Чай з медом смачніший, ніж чай без цукру.

literally looks like:

Tea with honey tastier than tea without sugar.

That is completely normal Ukrainian. Adding є here would usually sound unnecessary.

Because the preposition з meaning with requires the instrumental case.

The noun мед becomes медом in the instrumental singular:

• мед = honey
• медом = with honey

So:

• чай з медом = tea with honey

Because без meaning without requires the genitive case.

The noun цукор changes to цукру in the genitive singular:

• цукор = sugar
• цукру = of sugar / without sugar

So:

• чай без цукру = tea without sugar

Смачніший is the comparative form of смачний.

• смачний = tasty
• смачніший = tastier

Here it agrees with чай, which is masculine singular, so смачніший is also masculine singular.

Related forms would be:

• смачніша for a feminine noun
• смачніше for a neuter noun
• смачніші for plural

So this is the same basic idea as English tasty → tastier.

Yes, you could, but смачніший is more natural here.

Ukrainian often has two ways to make a comparative:

• a simple comparative: смачніший
• an analytical comparative: більш смачний

Both are grammatically possible, but the simple form is usually shorter and more natural in everyday speech.

Ніж means than in a comparison.

So:

• смачніший, ніж... = tastier than...

It introduces the second part of the comparison:

• Чай з медом смачніший, ніж чай без цукру.

This is a very common way to build comparisons in Ukrainian.

Yes. Ukrainian often uses either:

• смачніший, ніж...
• смачніший за...

So you can also say:

Чай з медом смачніший за чай без цукру.

Both are correct. For an English speaker, ніж often feels easier at first because it matches English than more directly.

Because in standard Ukrainian, a comparison introduced by ніж is normally separated with a comma.

So:

• смачніший, ніж...

That comma is expected in normal writing.

Because the sentence is comparing one kind of tea with another kind of tea, and repeating чай makes that explicit and natural.

• чай з медом
• чай без цукру

Ukrainian often repeats the noun in this kind of comparison instead of dropping it the way English sometimes does.

Not completely. Ukrainian word order is flexible, but this sentence uses a very neutral, natural order:

• thing being discussed: Чай з медом
• comparative: смачніший
• comparison part: ніж чай без цукру

You can move parts around for emphasis, but this version is the safest and most standard for a learner.

Because Ukrainian has no articles.

So чай can mean:

• tea
• a tea
• the tea

The exact meaning depends on context. English speakers often notice this right away, because English requires articles but Ukrainian does not.

З, із, and зі are variants of the same preposition. The choice usually depends on pronunciation and what sounds easiest before the next word.

Before медом, simple з sounds natural and smooth:

• з медом

So this is mostly about euphony, not a difference in meaning.