Learn Turkish: Anladım ki hayaletlerin kanı yokmuş. - I understood that ghosts apparently do not have blood.

In this lesson, ki acts just like the English word 'that' to introduce a realization. You state your action first (anladım - I understood or realized), add ki, and then explain what you realized in the rest of the sentence.

Doesn't Turkish usually put the main verb at the very end of the sentence?

Yes, standard Turkish word order puts the verb last. However, ki is a conjunction borrowed from Persian, and it brings its own word order rules. When you use ki to mean 'that', the main verb (anladım) comes before it, and the full phrase explaining it comes after.

How does hayaletlerin kanı yok translate to 'ghosts do not have blood'?

To say someone has or does not have something, Turkish uses a possessive structure with var (exists) or yok (does not exist). Literally, this says 'the ghosts' blood is non-existent.' hayaletlerin adds the owner genitive suffix (-in), and kanı adds the possessed suffix (-ı) to kan (blood).

Why use yokmuş here instead of just yok?