Yıllık ücret ödenmezse koruma süresi sona eriyor.

A very close breakdown is:

• yıllık = annual, yearly
• ücret = fee
• ödenmezse = if it is not paid
• koruma süresi = protection period / term of protection
• sona eriyor = comes to an end, expires

So literally, it is something like:

• If the annual fee is not paid, the protection period comes to an end.

A natural English translation is:

• If the annual fee is not paid, the protection period expires.

Ödenmezse is made of several parts:

• öde- = pay
• -n- = passive marker
• -mez = negative aorist / general negative
• -se = if

So:

• öde- → pay
• öde-n- → be paid
• öden-mez → is not paid / does not get paid
• ödenmez-se → if it is not paid

So ödenmezse means:

• if it is not paid

This is a very common structure in Turkish for formal statements, rules, and conditions.

Because the sentence focuses on the fee, not on the person who should pay it.

• Yıllık ücret ödenmezse... = If the annual fee is not paid...
• Active would be something like Birisi yıllık ücreti ödemezse... = If someone does not pay the annual fee...

Turkish often uses the passive in official, legal, and procedural language when the person doing the action is not important or not stated.

So the passive makes the sentence sound more formal and impersonal.

-se / -sa is the conditional ending, usually meaning if.

In this sentence:

• ödenmezse = if it is not paid

Examples:

• Gelirse haber ver. = If he/she comes, let me know.
• Yağmur yağarsa çıkmayız. = If it rains, we will not go out.

So here, the first part of the sentence sets up the condition:

• If the annual fee is not paid...

-mez is the negative form of the aorist, which often expresses:

• general truths
• habitual actions
• rules
• timeless statements

So:

• öder = pays / does pay
• ödemez = does not pay
• in the passive: ödenir = is paid, ödenmez = is not paid

In legal or formal language, Turkish often uses this form for rule-like statements:

• Ücret ödenmezse... = If the fee is not paid...
• Başvuru yapılmazsa... = If an application is not made...

Sona ermek is a fixed expression meaning:

• to come to an end
• to end
• to expire

Here:

• son = end
• sona = to the end / into an end-state
• ermek = to reach, to come to

So sona ermek literally means something like to reach its end.

In modern Turkish, this is a very common way to say that something ends formally or officially:

• Toplantı sona erdi. = The meeting ended.
• Sözleşme sona eriyor. = The contract is ending / expires.

So koruma süresi sona eriyor means:

• the protection period comes to an end
• more naturally, the protection period expires

This is a very good question, because Turkish often uses the present continuous form in places where English uses a simple present.

• eriyor is from ermek
• literally it looks like is ending

But in Turkish, the -yor form can also be used for:

• general statements
• regular processes
• official or factual descriptions

So in this sentence, sona eriyor does not necessarily mean it is ending right now at this second. It can mean:

• ends
• expires
• comes to an end

This is especially common in explanatory, formal, or legal language.

Because koruma süresi is a noun phrase built with the Turkish possessive construction.

It works like this:

• koruma = protection
• süre = period, duration
• süresi = its period / the period of

So koruma süresi literally means:

• the period of protection

This structure is extremely common in Turkish:

• ders kitabı = course book / the book of the course
• yaz tatili = summer vacation / the vacation of summer
• otobüs durağı = bus stop / the stop of the bus

So koruma süresi is the normal way to say protection period or term of protection.

In this sentence, yıllık ücret is the subject of the passive clause:

• Yıllık ücret ödenmezse...
• If the annual fee is not paid...

Because it is the subject, it does not need the accusative ending.

Compare:

• Yıllık ücret ödenmezse... = If the annual fee is not paid...
• Yıllık ücreti ödemezse... = If he/she does not pay the annual fee...

In the second sentence, ücreti has the accusative because it is the direct object of the active verb ödemek.

So the form changes depending on whether the sentence is passive or active.

Yıllık means:

• annual
• yearly

It comes from yıl = year, plus a suffix that forms adjectives.

Examples:

• yıllık ücret = annual fee
• yıllık gelir = annual income
• yıllık izin = annual leave

So yıllık ücret is simply:

• annual fee

The sentence as given is the most natural neutral order, especially in formal writing:

• Yıllık ücret ödenmezse koruma süresi sona eriyor.

This follows a common Turkish pattern:

• condition first
• main result second

So:

• If the annual fee is not paid, the protection period expires.

You could move parts around for emphasis, but the original order is the clearest and most standard, especially in legal or administrative language.

Both can work, but expires is often the best natural translation in this context.

Why?

Because koruma süresi is a formal time period connected to legal protection, rights, or registration. In English, when a legal or official period finishes, we often say it expires.

So:

• ends = correct
• comes to an end = very close to the Turkish
• expires = often the most natural legal/formal English choice

Yes. It sounds quite formal, official, and administrative.

That comes from several features:

• passive verb: ödenmezse
• abstract noun phrase: koruma süresi
• formal expression: sona eriyor

This is the kind of sentence you might see in:

• legal texts
• government notices
• regulations
• patent or trademark information
• official instructions

In everyday conversation, a speaker might choose a simpler phrasing, but in official Turkish this sentence sounds completely natural.