Retumilo elŝutas datumojn; tial mi ne malkonektos la aparaton.

Retumilo means web browser.

It is built from:

• reto = network, internet
• retumi = to browse the web, surf the internet
• -ilo = a tool or instrument used for doing something

So retumilo is literally a tool for web-browsing.

In Esperanto, the simple present tense often covers both:

• downloads
• is downloading

So Retumilo elŝutas datumojn can naturally mean The browser downloads data or The browser is downloading data, depending on context.

English usually distinguishes simple present and present progressive more strictly than Esperanto does.

The prefix el- often gives the idea of out.

So:

• ŝuti in modern computer-related Esperanto is associated with transferring data
• elŝuti = download literally pull out / transfer out
• alŝuti = upload literally transfer to

So elŝutas datumojn means downloads data.

Because it is:

• plural → -j
• the direct object of the verb → -n

Breakdown:

• datumo = one datum / one piece of data
• datumoj = data, multiple data items
• datumojn = the direct-object form of datumoj

Since the browser is downloading the data, datumojn is the thing being downloaded.

Yes. In Esperanto, datumo can be a singular noun meaning a datum, a data item, or a piece of information.

So:

• datumo = one item
• datumoj = multiple items, data

This is more straightforward than modern English, where data is often treated as an uncountable noun.

Tial means therefore, for that reason, or that’s why.

It points back to the first clause and gives the result:

• Retumilo elŝutas datumojn = the browser is downloading data
• tial mi ne malkonektos la aparaton = therefore I will not disconnect the device

So tial is showing cause and result.

The semicolon separates two closely related independent clauses.

Both parts could stand on their own:

• Retumilo elŝutas datumojn.
• Tial mi ne malkonektos la aparaton.

Using a semicolon shows a strong connection between them. This is similar to English punctuation.

It has three parts:

• konekti = to connect
• mal- = opposite
• -os = future tense

So:

• konekti = connect
• malkonekti = disconnect
• malkonektos = will disconnect

With ne, it becomes will not disconnect.

In Esperanto, ne normally comes before the word or part of the sentence being negated.

So:

• mi malkonektos = I will disconnect
• mi ne malkonektos = I will not disconnect

That placement is very normal and straightforward in Esperanto.

Because la aparaton is the direct object of malkonektos.

The speaker is not disconnecting the device, so aparaton gets the accusative ending -n.

Breakdown:

• aparato = device
• la aparato = the device
• la aparaton = the device, as the direct object

La means the, so it refers to a specific device that is known from the context.

Without la, aparaton would sound more like a device or some device, depending on context. Here, the device is more natural because the speaker likely has a particular device in mind.

Yes. Esperanto word order is fairly flexible, as long as the grammar endings make the roles clear.

For example, you could also say:

• Tial mi ne malkonektos la aparaton.

That would still mean the same thing.

However, the original order works well because it first states the reason, then gives the consequence.

Yes, that is the practical meaning.

Literally it says I will not disconnect the device, and in context that implies the speaker will keep it connected because the browser is downloading data.

So the sentence is not just about a future action being avoided; it also suggests a reasoned decision to leave the connection alone.