Learn Turkish: Kiminle konuşsam, yeni bir şiveyi hafızamda tutamıyorum. - No matter who I speak to, I cannot keep a new dialect in my memory.

This is the universal concessive conditional structure you are currently learning. By combining a question word like kiminle (with whom) and a verb in the conditional form like konuşsam (if I speak), it creates the meaning of "no matter [question word]...". Literally, it feels like "With whom if I speak...", which naturally translates to "No matter who I speak to".

Why does yeni bir şive take the accusative ending -yi if bir usually makes things indefinite?

Normally, indefinite direct objects with bir (a/an) do not take the accusative marker. However, adding it here to make yeni bir şiveyi means the speaker is talking about a specific indefinite object. They are not talking about the concept of dialects in general, but rather "a certain new dialect" they were just exposed to and are actively trying to remember.

Can you break down the suffixes in tutamıyorum?

The root is tut- (to hold or keep). The next letter, -a-, is the crucial marker for inability, meaning "cannot". Then comes the negative marker -mı-, which is normally "-ma-" but narrows to an "ı" sound because of the following suffix. Finally, we have the present continuous tense -yor- and the first-person ending -um. Together, they form "I cannot keep".

Why is it kiminle instead of just kimle?