Mi kontrolas la horaron ĉiun lundon kaj ĉiun mardon.

In Esperanto, verbs change ending to show tense and mood.

• -i = infinitive, like to check
• -as = present tense, like check / am checking
• -is = past tense
• -os = future tense

So kontroli means to check, while kontrolas means check or am checking.

In this sentence, Mi kontrolas means I check.

Usually, no. This is a very common false friend for English speakers.

In Esperanto, kontroli usually means:

• to check
• to inspect
• to verify

So Mi kontrolas la horaron means I check the schedule, not I control the schedule.

If you mean control in the sense of manage, govern, or operate, Esperanto often uses other words, depending on context, such as regi, stiri, or mastrumi.

La is Esperanto’s definite article, meaning the.

So:

• horaro = a schedule / schedule
• la horaro = the schedule

The sentence uses la horaron because it refers to a specific schedule that the speaker has in mind.

Also remember:

• Esperanto has la for the
• Esperanto does not have a separate word for a/an

The ending -n marks the direct object in Esperanto.

Here, the thing being checked is the schedule, so la horaro becomes la horaron.

Breakdown:

• Mi kontrolas = I check
• la horaron = the schedule

Since the schedule is what receives the action of checking, it takes -n.

Great question. In Esperanto, -n is not only for direct objects.

It is also often used for certain expressions of:

• time
• measure
• direction

Here, ĉiun lundon and ĉiun mardon are time expressions, meaning every Monday and every Tuesday.

So:

• ĉiu lundo = every Monday, as a basic form
• ĉiun lundon = every Monday, used as a time expression in the sentence

This is a standard Esperanto pattern. English does not show this with a special ending, but Esperanto often does.

Because ĉiu changes to match the grammar of the noun phrase it belongs to.

Here:

• ĉiu = each / every
• ĉiun = accusative form of ĉiu

Since the time expression takes -n, the modifier takes it too:

• ĉiu lundo → ĉiun lundon
• ĉiu mardo → ĉiun mardon

In Esperanto, words that belong together in a noun phrase usually match in this way.

Because Esperanto normally uses the singular after ĉiu when the meaning is each individual one or every.

So:

• ĉiun lundon = every Monday
• ĉiun mardon = every Tuesday

This is the most natural way to say it.

The idea is not all Mondays as a group, but each Monday, one by one.

It is repeated because the sentence has two separate time expressions:

• ĉiun lundon
• ĉiun mardon

Repeating ĉiun makes the structure clear and natural: every Monday and every Tuesday.

A learner should definitely use the repeated form, because it is clear and standard.

In Esperanto, days of the week are normally written in lowercase:

• lundo
• mardo
• merkredo
• etc.

This is different from English, where Monday and Tuesday are capitalized.

So lundon and mardon are written correctly here.

Yes. Esperanto word order is more flexible than English because endings show the grammar.

This sentence uses a very normal, neutral order:

• Mi kontrolas la horaron ĉiun lundon kaj ĉiun mardon.

But other orders are also possible, for example to emphasize the time:

• Ĉiun lundon kaj ĉiun mardon mi kontrolas la horaron.

Both are understandable. The original order just sounds straightforward and natural.