الدفتر اللي على الطاولة تبع اخي، بس القلم تبعي.

Because Levantine Arabic usually drops the present-tense verb to be.

So:

• الدفتر اللي على الطاولة تبع أخي = The notebook on the table is my brother’s
• القلم تبعي = The pen is mine

This is very normal in Arabic. In the present tense, Arabic often just puts the subject and the description/predicate next to each other.

اللي is the everyday Levantine relative word meaning that, which, or who.

So:

• الدفتر اللي على الطاولة = the notebook that is on the table

A useful thing to know: in Levantine, اللي usually stays the same for all genders and numbers. Unlike Standard Arabic, you do not need different forms like الذي and التي in normal speech.

Because the meaning changes.

• الدفتر على الطاولة usually means The notebook is on the table
• الدفتر اللي على الطاولة means the notebook that is on the table

So اللي turns على الطاولة into a description of the notebook, not the main statement of the sentence.

تبع is a very common Levantine way to show possession. It means something like belonging to or of.

So:

• تبع أخي = my brother’s / belonging to my brother

In this sentence, الدفتر اللي على الطاولة تبع أخي means the notebook belongs to your brother.

This is a colloquial structure and is extremely common in spoken Levantine.

Because the possessor is expressed in two different ways:

• تبع أخي = belonging to my brother
  Here the possessor is a full noun phrase: أخي
• تبعي = mine
  Here the possessor is a pronoun, so Arabic attaches a suffix

Some common forms are:

• تبعي = mine
• تبعك = yours
• تبعه = his
• تبعها = hers
• تبعنا = ours

So القلم تبعي literally means the pen [is] mine.

Because الدفتر and القلم are masculine nouns.

In many Levantine varieties, تبع agrees with the thing being possessed:

• masculine: تبع
• feminine: تبعت

So you get:

• القلم تبعي = the pen is mine
• السيارة تبعتي = the car is mine

Since دفتر and قلم are masculine, تبع / تبعي fits.

Regional variation exists, but this is the basic pattern many learners are taught.

Yes, بس can mean both but and only/just, depending on context.

Here it means but, because it contrasts two ideas:

• the notebook is your brother’s
• but the pen is yours

So in this sentence, بس is functioning as a conjunction.

It is mainly Levantine-style.

The most clearly colloquial Levantine parts are:

• اللي instead of Standard Arabic الذي / التي
• تبع as a possession marker
• بس for but

Other words like الدفتر, على, الطاولة, and القلم are common in both Standard Arabic and dialects.

So a learner should recognize this as normal spoken-style Arabic, not formal written Standard Arabic.

Very often, على الطاولة becomes عالطاولة in natural speech.

So the sentence may sound more like:

• الدفتر اللي عالطاولة تبع أخي، بس القلم تبعي

This contraction is extremely common in Levantine:

• على البيت → عالبيت
• على الطريق → عالطريق

So if you hear عالـ, it often comes from على الــ.

Yes. Arabic has more than one way to show possession.

A more formal or tighter possessive structure is the idafa type, such as:

• دفتر أخي = my brother’s notebook

But تبع is very useful in speech, especially when the noun phrase is long:

• الدفتر اللي على الطاولة تبع أخي

That sounds very natural in Levantine. Using تبع can make long phrases easier to build.

Because the speaker is talking about specific items:

• الدفتر = the notebook
• القلم = the pen

In الدفتر اللي على الطاولة, the notebook is already specific because it is identified by the phrase اللي على الطاولة.

And القلم تبعي means the pen is mine, referring to a particular pen. If you said something more like قلم تبعي, that could sound more like a pen of mine or one of my pens, depending on context.