Türkçede belirli nesneler -ı/-i eki alır; mesela interneti kullanıyorum.

Türkçede means in Turkish.

It is built like this:

• Türkçe = Turkish
• -de = in / at / on

So Türkçede literally means in the Turkish language.

A small spelling note: Turkish language names like Türkçe, İngilizce, Almanca usually take suffixes directly, so you write Türkçede, not Türkçe'de.

Belirli nesneler means definite objects or more broadly specific direct objects.

In Turkish grammar, this usually refers to a direct object that the speaker has a particular thing in mind. That is why it often gets the accusative ending.

For example:

• kitap okuyorum = I am reading a book / books in a general or nonspecific sense
• kitabı okuyorum = I am reading the book / that particular book

So belirli is often taught as definite, but specific is sometimes an even better way to think about it.

This is the Turkish accusative ending, used for definite/specific direct objects.

In the sentence, interneti is:

• internet
  • -i

So interneti kullanıyorum means that internet is the direct object and it is being treated as definite/specific.

A very important point: the full accusative ending is not just -ı/-i. In full, it is:

• -(y)ı
• -(y)i
• -(y)u
• -(y)ü

The vowel changes because of vowel harmony, and the y appears when needed after a vowel.

Because this is a simplified way of introducing the idea.

Many beginner explanations say -ı/-i as a shortcut, but the full rule is wider. In real Turkish, you must choose among four vowel forms:

• -ı
• -i
• -u
• -ü

Examples:

• kitap → kitabı
• ev → evi
• okul → okulu
• gül → gülü

So the sentence is correct as a basic explanation, but it is not the complete picture.

Because of vowel harmony.

To choose the accusative vowel, Turkish looks at the last vowel of the word. In internet, the last vowel is e. After e, the correct accusative vowel is i.

So:

• internet → interneti

Very roughly, the pattern is:

• last vowel a or ı → -ı
• last vowel e or i → -i
• last vowel o or u → -u
• last vowel ö or ü → -ü

The version with the accusative ending, interneti kullanıyorum, makes the object definite/specific.

The version without it, internet kullanıyorum, is more general or nonspecific.

A useful way to feel the contrast is:

• internet kullanıyorum = I use internet / I am using internet in a general sense
• interneti kullanıyorum = I am using the internet / that internet service / a specific instance of it

With some nouns, this contrast is very clear:

• kitap okuyorum = I am reading a book / reading books
• kitabı okuyorum = I am reading the book

So the accusative ending is not just a random object marker; it adds a meaning of specificity.

No. Only definite/specific direct objects take the accusative ending.

Compare:

• elma yiyorum = I am eating apples / an apple in a nonspecific sense
• elmayı yiyorum = I am eating the apple

So if the object is indefinite, generic, or nonspecific, Turkish often leaves it bare, with no accusative ending.

This is one of the biggest differences from English. English often uses word order and articles like a and the, while Turkish often uses the bare noun vs. accusative-marked noun contrast.

You use y when the noun ends in a vowel.

That is why the full accusative suffix is written as -(y)ı / -(y)i / -(y)u / -(y)ü.

Examples:

• araba → arabayı
• kapı → kapıyı
• öğrenci → öğrenciyi
• su → suyu

But if the word ends in a consonant, you do not add y:

• internet → interneti
• kitap → kitabı
• okul → okulu

So interneti has no y because internet ends in t.

Because in Turkish, a third-person plural subject does not always require a plural verb.

With general statements, non-human subjects, or broad grammatical rules, Turkish very often uses the singular verb form:

• Çocuklar geldi = The children came
• Arabalar pahalı oldu = The cars became expensive
• Belirli nesneler ek alır = Definite objects take a suffix

You can sometimes see plural agreement too, but the singular is very normal here. In grammar explanations like this one, singular alır sounds natural.

Ek means suffix or affix.

So -ı/-i eki means the -ı/-i suffix.

The form eki is the way Turkish commonly builds this kind of noun phrase in grammar language. You will often see similar expressions such as:

• çoğul eki = plural suffix
• iyelik eki = possessive suffix
• hal eki = case suffix

So here, eki is just grammatical terminology meaning suffix.

Kullanıyorum means I am using or sometimes simply I use, depending on context.

It breaks down like this:

• kullan- = use
• -ıyor = present continuous / progressive marker
• -um = I

So:

• kullanıyorum = I am using

Because of vowel harmony, the progressive marker can appear as:

• -ıyor
• -iyor
• -uyor
• -üyor

Here it is -ıyor, so the full form is kullanıyorum.