Learn Farsi: اصیل‌ترین گویش این منطقه خیلی غنی است. - The most authentic dialect of this region is very rich.

In Farsi, superlative adjectives (those ending in -tarin) are placed before the noun they modify, and they do not take an Ezafe. If you were using the base adjective, it would follow the noun with an Ezafe, as in guyesh-e asil (an authentic dialect).

What is the difference between guyesh and lahje?

Guyesh specifically means a 'dialect' (a regional variety of a language with its own distinct vocabulary and grammar). It comes from the present stem of goftan (to say). Lahje, on the other hand, translates to 'accent' and refers strictly to the pronunciation.

Does ghani mean 'rich' in the sense of having a lot of money?

Not usually. Ghani means rich in the sense of being abundant, deep, or culturally wealthy, which is why it pairs perfectly with a dialect, language, or culture. If you want to talk about a wealthy person, you would normally use puldar or sarvatmand.

What does the root word asil imply in this context, and can it be used for people?

Asil means authentic, pure, or original. Here, it implies the dialect is traditional and uncorrupted. It is also frequently used for people, where it means someone is noble, genuine, or comes from a highly respectable family background.