Mia abono komenciĝos morgaŭ.

In Esperanto, the future is usually shown by the verb ending -os, not by a separate word like English will.

So:

• komenciĝos = will start / will begin

You can break it down like this:

• komenc- = the root about beginning
• -iĝ- = become / get into a state
• -os = future tense

So the idea of will is already built into komenciĝos.

Komenciĝos is a future-tense verb.

More exactly, it comes from komenciĝi, which means to begin / to start in the sense of to become started.

Its parts are:

• komenc- = begin/start
• -iĝ- = become, get, come to be
• -os = future tense

So komenciĝos literally has the sense of will become started, which in normal English is just will begin or will start.

A learner often notices the -iĝ- and wonders why it is there.

The suffix -iĝ- often makes a verb intransitive or shows that something enters a new state. Here, the subscription is not starting something else; it is itself starting.

So:

• komenci can mean to start something
• komenciĝi means to start/begin oneself, or to become started

In this sentence, Mia abono is the thing that begins, so komenciĝos is very natural.

-iĝ- is a very common suffix. It often means:

• become
• get
• come to be
• or it turns something into an intransitive change-of-state verb

For example:

• ruĝa = red

• ruĝiĝi = to become red

• malfermi = to open something
• malfermiĝi = to open, to become open

So komenciĝi follows the same pattern: to become started, which we usually translate more naturally as to begin.

Because abono is the subject, not the direct object.

In Esperanto:

• -n usually marks the direct object
• the subject has no -n

Here:

• Mia abono = the thing that will begin
• komenciĝos = will begin
• morgaŭ = tomorrow

There is no direct object in this sentence, so no -n is needed.

Usually, no.

In Esperanto, a possessive like mia, via, lia, and so on already makes the noun definite enough, so la is normally not used.

So:

• mia abono = my subscription

Using la mia abono would normally sound unnatural in a simple sentence like this.

Abono is a noun meaning something like:

• subscription
• sometimes membership, depending on context

It comes from the root abon-.

Related forms include:

• aboni = to subscribe
• abonanto = subscriber
• abonejo or other derived forms may appear depending on context

So in this sentence, mia abono most naturally means my subscription.

Yes. Esperanto word order is fairly flexible, especially with adverbs like morgaŭ.

The original sentence is:

• Mia abono komenciĝos morgaŭ.

But these are also possible:

• Morgaŭ mia abono komenciĝos.
• Mia abono morgaŭ komenciĝos.

The basic meaning stays the same. The original version is a very normal, straightforward order.

Esperanto stress is always on the second-to-last syllable.

So komenciĝos is divided like this:

• ko-men-ci-ĝos

The stress falls on ci:

• ko-men-CI-ĝos

A few pronunciation notes:

• c sounds like ts in cats
• ĝ sounds like the j in judge
• j and ĝ are different letters, so be careful not to confuse them

So komenciĝos sounds approximately like ko-men-TSI-jos, with the stress on tsi.

Mia is the possessive adjective meaning my.

It matches the noun it describes:

• mia abono = my subscription

Because abono is singular, mia stays singular too. If the noun were plural, you would use miaj:

• miaj abonoj = my subscriptions

So mia is simply the correct possessive form for one abono.