“I see you!” = Σε βλέπω but “ I talk to you!” Σου μιλάω
Some verbs have a direct object (like «βλέπω») while others indirect (like «μιλάω») and some can get both, (like «παίρνω») Wow! Slowly you will distinguish them.
I hope that this image will help you!
Remember we put them before the verb!