Using of commas
Between items in a series:
Ex: The experience demanded blood, sweat, and tears.

Between coordinate adjectives (more than one adj):
Ex: We listened to an absorbing, frightening account of the event.

Before coordinating conjuctions joining independent clauses:
Ex: Congress passed the bill by a wide margin, and the president signed it into law.

Around parenthetical elements:
Ex: The invention, the first in a series during that decade, completely changed people's lives.

Using of semicolons (;):
Between items in series when some of the items require internal commas:
Ex: There are four universities in Syria: Al-Baath, Homs; Aleppo U, Aleppo; Damas U, Damas; Tishreen U, Latakia.

Between closely related independent clauses not joined by coordinating conjuctions:
Ex: On the one hand, demand is steadily decreasing; on the other, production keeps inexplicably increasing.

Before coordinating conjunctions linking independent clauses that require a number of internal commas:
Ex: The overture begins with a brooding, mournful passage in the strings and woodwinds, one of the composer's most passionate statements; but the piece concludes with a burst of lively, spirited, almost comic music in the brass and percussion

الف الف الف شكر الك رولى لانو لبيتي طلبي ..

كلك ذوق فعلا كنت بحاجة لاعرف هالقواعد .. و خاصة Using of semicolons

صرت سنة 3 و هلق حتى عرفتها