Learn Turkish: Eski yapılar yıkılalı sokaklar daha geniş oldu. - The streets have become wider since the old structures were demolished.

Let's break it down! The root verb is yıkmak (to demolish or destroy). First, we add the passive suffix -ıl- to make yıkılmak (to be demolished). Finally, we add the suffix from this lesson, -alı, to get yıkılalı (since being demolished).

Could I use binalar instead of yapılar here?

Yes, you absolutely can! Bina is a common word specifically meaning "building." Yapı comes from the Turkish verb yapmak (to make or build) and means "structure," but it is very commonly used to mean "building" in sentences like this.

The sentence has two different subjects (eski yapılar and sokaklar). Is it okay to use -alı when the subject changes?

Yes! The suffix -alı just marks the event that starts the clock. The first part (eski yapılar yıkılalı) sets the time: "since the old structures were demolished." The main sentence (sokaklar daha geniş oldu) tells us what has happened since that time. The subjects of the two actions do not have to match.

Why does the sentence use oldu at the end instead of just a "to be" ending?

In Turkish, the verb olmak often means "to become." Because we are talking about a physical change that happened since the buildings were demolished, we say daha geniş oldu (they became wider) rather than just stating a static fact with a "to be" ending.