جراباتي الجداد جنب الحذاء الاسود.

It is:

• جرابات = socks
• ـي = my

So جراباتي means my socks.

In Levantine, جراب is a common word for sock, and جرابات is its plural.

الجداد means the new ones / new and is the plural form of جديد.

Because جراباتي is plural (my socks), the adjective is plural too:

• جديد = new, masculine singular
• جديدة = new, feminine singular
• جداد = new, plural in Levantine colloquial

So جراباتي الجداد = my new socks.

That is a very common learner question, especially if you know some Modern Standard Arabic.

In Levantine colloquial, non-human plurals often take a regular plural adjective, so:

• جراباتي الجداد = natural Levantine

In MSA, a non-human plural often takes a feminine singular adjective, so you would more likely see:

• جواربي الجديدة

So الجداد is a good colloquial Levantine choice.

Because جراباتي is already definite by possession. My socks are definite even without الـ.

In Arabic, adjectives have to match the noun in definiteness. So if the noun phrase is definite, the adjective is definite too.

That is why you get:

• جراباتي الجداد = my new socks

not just جراباتي جداد in this kind of phrasing.

Because that is the normal Arabic pattern:

• noun + adjective

So Arabic says, literally:

• socks-my the-new

rather than my new socks.

The same thing happens in:

• الحذاء الأسود = the black shoe

In Arabic, the verb to be is usually omitted in the present tense.

So the sentence literally looks like:

• My new socks next to the black shoe

but it means:

• My new socks are next to the black shoe

This is completely normal in Arabic.

جنب means next to, beside, or by.

So:

• جنب الحذاء = next to the shoe

It works very naturally as a location word in Levantine. You may also hear related forms like بجنب in some varieties.

Because in Arabic, if the noun is definite, the adjective must also be definite.

So:

• الحذاء = the shoe
• الأسود = the black

Together:

• الحذاء الأسود = the black shoe

Also, أسود is masculine singular here because حذاء is masculine singular.

In careful standard spelling, it should be:

• الأسود

with the hamza.

But in casual typing, many Arabic speakers leave hamzas out, so:

• الاسود

is extremely common online and in informal writing.

It is understandable and natural enough, but it is a little mixed in register.

• جراباتي الجداد sounds nicely colloquial/Levantine.
• الحذاء is more standard or formal-sounding.

In everyday Levantine speech, many speakers might use a more regional everyday word for shoe, depending on where they are from.

A more standard Arabic version would be:

• جواربي الجديدة بجانب الحذاء الأسود

So the sentence you have is very understandable, but not the most purely everyday spoken version possible.

A rough pronunciation is:

• jraabaati l-jdaad janb il-ḥizaa l-aswad

A few notes:

• جراباتي starts with a cluster like jr-
• الجداد sounds like l-jdaad
• جنب is roughly janb or jamb, depending on speaker/region
• pronunciation can vary a bit across Levantine dialects

So the rhythm is roughly:

• jraabaati l-jdaad janb il-ḥizaa l-aswad