Mehdi would jump for joy every time his parents promised him to visit his grandmother, who lives in one of the old city's alleys. He used to compare between the city streets and his neighbourhood streets, and he could only see a narrow winding road that widens one time, and tightens at another.

I have to say that the second sentence has mistakes, and it almost doesn't make any sense. What is it that you are trying to say exactly?

The use of the word (انهج) is wrong - I guess. And, I believe you meant (تضيق) when you wrote down (تصيف)

I hope this helps.

Thank's a lot! My teacher is from Tunisia, so yes...maybe it has tunisian words! Sorry for my mistakes and thank you all for your help, it was difficult to me

The words are not really Tunisian , it's just a ... preference on the part of Tunisian people. For example we call a city square "ساحة" while it is called "ميدان" in Egypt.

Mehdi was a joy to fly whenever promised my father to visit his grandmother, who lives one of the alleys of the old city. It was located between the city's rivers and vast rivers neighborhood, but does not see a path winding accommodate weak and sometimes narrowing the last.

Apart from a few words with typos , her sentence is well written.

Perhaps she found this sentence in a Tunisian (or otherwise north african) book. Here we some times use the word 

نهج 

for street , instead of 

شارع

Of course both have the same meaning. The plural of نهج is أنهج.

Please be careful as to write the letter أ instead of ا when necessary. It may be confusing.

تصيف is a mistake , she meant تضيق.