Learn Turkish: O vakfa çok para akıtılırdı. - A lot of money would be poured into that foundation.

Let's take it piece by piece! The root is akmak (to flow). First, we add the causative suffix -ıt to make akıtmak (to cause to flow, meaning to pour). Next, we add the passive suffix -ıl to make akıtılmak (to be poured). Finally, we attach the tense endings. The causative-passive double derivation (ak-ıt-ıl) transforms a simple verb of motion into an action being done to something by an unnamed agent.

Why use the ending -ırdı here instead of just the regular past tense?

The combination of the aorist suffix -ır and the past tense suffix -dı creates a "past habitual" tense. In English, we translate this as "used to" or "would" do something in the past. If the sentence just used akıtıldı, it would mean money was poured there a single time. Using akıtılırdı implies it happened repeatedly or as a general rule over a period of time.

The dictionary word for foundation is vakıf. Why does it become vakfa instead of vakıfa?

This is a great example of vowel drop (vowel omission). Many two-syllable Turkish words, especially those of Arabic origin like vakıf, drop their second vowel when a suffix starting with a vowel is attached. Here, vakıf gets the dative suffix -a (meaning "to"), so the ı drops out, leaving us with vakfa.