هديك الشقة يلي جنب شقة جارتي فاضية.

هديك means that and it is feminine singular.

It matches الشقة, because شقة is a feminine noun in Arabic.

A quick comparison:

• هاي / هيدي / هادي الشقة = this apartment
• هديك الشقة = that apartment

The masculine equivalent is usually هداك.

In Levantine, you may also hear the demonstrative after the noun, for example الشقة هديك.

يلي is the Levantine relative word meaning that / which / who.

So:

• الشقة يلي جنب شقة جارتي = the apartment that is next to my neighbor’s apartment

A very common variant is اللي. In Levantine, يلي and اللي do the same job.

One useful thing for learners: unlike English, this word does not change for gender or number. The same يلي / اللي can be used with masculine, feminine, singular, or plural nouns.

In Levantine Arabic, the verb to be is usually left out in the present tense.

So:

• الشقة فاضية literally looks like the apartment empty
• but it means the apartment is empty

The same idea appears inside the relative clause:

• يلي جنب شقة جارتي literally that next to my neighbor’s apartment
• naturally understood as that is next to my neighbor’s apartment

If you wanted the past, you would use a verb, for example:

• كانت فاضية = it was empty

Because here فاضية is the predicate: it means is empty, not the empty.

Compare these two patterns:

• الشقة الفاضية = the empty apartment

  • here الفاضية is a normal adjective directly describing the noun

• الشقة ... فاضية = the apartment ... is empty

  • here فاضية is the predicate of the sentence

So in your sentence, فاضية comes after the whole noun phrase and does not take الـ.

Because الشقة is feminine singular, and Arabic adjectives agree with the noun they describe.

So:

• شقة → فاضية
• بيت → فاضي

Examples:

• البيت فاضي = the house is empty
• الشقة فاضية = the apartment is empty

جنب means beside / next to.

In Levantine, it can work directly with the following noun, so you do not need a separate word for to.

So:

• جنب شقة جارتي = next to my neighbor’s apartment

This is very normal Arabic structure.

Because جنب جارتي would mean next to my female neighbor herself, not next to my female neighbor’s apartment.

The sentence specifically wants my neighbor’s apartment, so it says:

• شقة جارتي = my female neighbor’s apartment

This is an iḍāfa (construct phrase), a very common Arabic possession structure:

• شقة = apartment
• جارتي = my female neighbor

Together: شقة جارتي = my female neighbor’s apartment

Because in an iḍāfa structure, the first noun usually does not take الـ.

So:

• not الشقة جارتي
• but شقة جارتي

Even without الـ on شقة, the whole phrase is still definite, because جارتي is definite (my neighbor).

So شقة جارتي is understood as a specific apartment: my female neighbor’s apartment.

It specifically means my female neighbor.

• جارتي = my female neighbor
• جاري = my male neighbor

English usually does not show the gender in my neighbor, but Arabic does.

So this sentence is talking about the apartment next to a female neighbor’s apartment.

Because the final ـة (taa marbuuTa) changes its pronunciation depending on the context.

When the word stands alone, it is usually pronounced like -a or -e:

• شقة ≈ shaqqa / sha''a

But in an iḍāfa or before certain endings, the hidden t sound appears:

• شقة جارتي ≈ shaqqet jaarti

So that t sound is expected and completely normal.

A common pronunciation would be roughly:

hadiik ish-shaʔʔa yalli jamb shiʔʔet jaartii faaḍye

A few pronunciation notes:

• الـ before ش is pronounced ish-
• يلي may also sound like illi or yalli
• ق in شقة is often pronounced as a glottal stop in many urban Levantine accents
• فاضية is often heard as faaḍye or faaḍiye

So the overall rhythm is something like:

hadiik ish-sha'a yalli jamb shi'et jaarti faaDye