Learn Arabic (Modern Standard): إما أن تشتري نفس الماركة أو تشتري تقليدا. - You either buy the same brand, or you buy an imitation.

When نفس is placed before a definite noun in an Idafa (possession) structure, it means "the same [noun]". Literally, it is like saying "the self of the brand", but it naturally translates to "the same brand". The second word, الماركة, must have the definite article ال for this meaning to work.

How does the "either... or..." structure work in this sentence?

The basic phrase for "either... or..." is إما ... أو. Because the first option here is an action verb ("you buy"), we must use أن before it, creating إما أن تشتري (literally "either that you buy"). You then follow أو with the second verb option.

Why does the word for "imitation" (تقليدا) end with an extra alif (ا)?

تقليدا is the direct object of the verb تشتري (you buy). In Arabic, an indefinite direct object takes the accusative case, which is marked by a double fatha (tanwin fatha) on the final letter. For most words, this spelling rule requires adding a silent alif (ا) to the very end.

Is ماركة an original Arabic word?

No, it is a very common loanword used to mean "brand" or "make" (like a clothing or car brand), coming from the European "marca". It was adapted into Arabic with a taa marbuta (ة) at the end, making it behave grammatically just like a standard feminine noun.