Learn Hardcore Turkish: Ben video izliyorum.

Ben means “I.” It’s optional because Turkish is a pro-drop language: the verb ending -um in izliyorum already signals first-person singular. You can simply say Video izliyorum and still mean “I’m watching a video.”

What is the infinitive of izliyorum, and how is this form built?

The infinitive is izlemek (to watch). To form izliyorum:
1) Drop -mek → izle-
2) Add the progressive suffix -yor, vowel-harmonized to -iyor → izliyor
3) Add the first-person singular ending -um → izliyorum
Altogether izl-iyor-um = “I am watching.”

What do the suffixes -yor and -um indicate in izliyorum?

-yor marks the present continuous (progressive) aspect (equivalent to English “-ing”).
-um marks first-person singular (“I”).
Together, they form “I am …-ing.”

Why is there a y before the o in izliyorum?

The progressive suffix -yor begins with a vowel. Since the stem izle- ends in a vowel, Turkish inserts a buffer consonant y to avoid a vowel cluster:
izle + y + or + um → izliyorum.