La suko, kiun mi trinkas matene, estas malpli dolĉa ol la teo kun mielo.

La is the Esperanto definite article, meaning the.

In this sentence, both nouns are specific:

• La suko = the juice
• la teo kun mielo = the tea with honey

Esperanto uses la much like English uses the. It does not change for gender, number, or case, so it always stays la.

Kiun means which or that in this sentence.

The phrase:

kiun mi trinkas matene

means:

which I drink in the morning / that I drink in the morning

It introduces a relative clause describing la suko.

So the structure is:

• La suko ... estas malpli dolĉa...
• kiun mi trinkas matene = extra information about the juice

It is kiun because the relative pronoun is the direct object of trinkas.

Compare:

• mi trinkas la sukon = I drink the juice
• therefore: la suko, kiun mi trinkas... = the juice, which I drink...

The -n marks the direct object in Esperanto.

A useful test:

• Who is doing the drinking? mi
• What is being drunk? la suko
• So the relative word referring to la suko must take -n: kiun

The commas show that this is an inserted relative clause:

La suko, kiun mi trinkas matene, estas...

In English, this is similar to:

The juice, which I drink in the morning, is...

Esperanto often uses commas to clearly separate this kind of clause from the main sentence.

The main statement is:

La suko estas malpli dolĉa ol la teo kun mielo.

The middle part simply adds description.

Trinkas is the present tense form of trinki = to drink.

Esperanto tense endings are very regular:

• -as = present
• -is = past
• -os = future
• -us = conditional
• -u = command / jussive
• -i = infinitive

So:

• mi trinkas = I drink / I am drinking

Here, the present tense works naturally because it describes a habitual or general action: the juice that I drink in the morning.

Matene means in the morning.

The ending -e makes it an adverb. Esperanto uses adverbs for many time expressions.

Examples:

• mateno = morning
• matene = in the morning
• vespero = evening
• vespere = in the evening

So:

• mi trinkas matene = I drink in the morning

This is a very common and natural Esperanto pattern.

Yes, you could, but matene is usually more natural here.

Compare:

• matene = in the morning
• en la mateno = literally in the morning

Both can be understood, but Esperanto often prefers the simple adverb form for times of day.

So in this sentence, matene is the most idiomatic choice.

Malpli ... ol ... means less ... than ...

So:

• malpli dolĉa = less sweet
• ol la teo kun mielo = than the tea with honey

The full comparison is:

estas malpli dolĉa ol la teo kun mielo
= is less sweet than the tea with honey

Common comparison patterns in Esperanto:

• pli ... ol ... = more ... than ...
• malpli ... ol ... = less ... than ...
• tiel ... kiel ... = as ... as ...

Examples:

• pli granda ol = bigger than
• malpli varma ol = less warm than
• tiel bona kiel = as good as

Because it describes a noun: la suko.

• dolĉa = sweet (adjective)
• dolĉe = sweetly / in a sweet way (adverb)

In the sentence, we are saying what the juice is:

La suko estas malpli dolĉa...
= The juice is less sweet...

Since dolĉa describes suko, it must be an adjective.

Also notice agreement:

• suko is singular
• so the adjective is singular too: dolĉa

If the noun were plural, the adjective would be plural too:

• La sukoj estas dolĉaj.

Because it is not a direct object here.

In:

La suko estas malpli dolĉa...

la suko is the subject, and dolĉa is a predicate adjective after estas.

Predicate adjectives agree with the noun in number and case, but here the subject is singular and not accusative, so the form is just:

dolĉa

You would only use -n on the adjective if the noun it agrees with were accusative.

Kun mielo means with honey.

• kun = with
• mielo = honey

So:

la teo kun mielo = the tea with honey

This phrase modifies teo, telling us what kind of tea is meant.

Because mielo is a noun: honey.

In kun mielo, the preposition kun is followed by a noun phrase:

• kun sukero = with sugar
• kun lakto = with milk
• kun mielo = with honey

If you said miela, that would be an adjective meaning honey-like or made of honey, which is not what is needed here.

Esperanto word order is fairly flexible, but this order is the most straightforward and natural.

The sentence is arranged like this:

• La suko = subject
• kiun mi trinkas matene = relative clause describing the subject
• estas = verb
• malpli dolĉa = predicate adjective
• ol la teo kun mielo = comparison phrase

Because Esperanto marks grammatical roles clearly, especially with -n, some rearrangement is possible. But for learners, this standard order is best.

It refers to la suko.

In Esperanto, a relative clause usually refers back to the nearest suitable noun before it. Here that noun is:

La suko

So:

La suko, kiun mi trinkas matene...
= The juice, which I drink in the morning...

It does not describe the tea, because the tea appears later in the sentence.

In careful written Esperanto, the commas are appropriate and normally expected around this inserted relative clause.

So this is the standard form:

La suko, kiun mi trinkas matene, estas malpli dolĉa ol la teo kun mielo.

Without the commas, the sentence would still probably be understood, but it would look less correct in normal writing.

Because all the nouns here are singular:

• suko = juice
• teo = tea
• mielo = honey

So there is no need for -j.

If you made them plural, you would add -j, and adjectives would agree:

• La sukoj, kiujn mi trinkas matene, estas malpli dolĉaj...

Here, though, everything is singular, so the forms stay singular.

Yes.

In English, relative clauses often allow either:

• the juice which I drink in the morning
• the juice that I drink in the morning

Esperanto uses kiu/kiun for this function, and it does not make the same which/that distinction English sometimes does.

So kiun here can be understood as either which or that, depending on how you prefer to translate it.