How to use just, ever, always, never, and yet?

We use just, ever, already ,never, and yet in present perfect tense?

Position of sentence  
They have just gone.
Have you ever been there?
Rita has already gone.
I have never seen them.

BUT
I have not finished yet. ( yet comes after the past participle)

Note: I have
          he/ she/it  has
         we/ they have

I have been to Chicago three times (you can add the number of times at the end of the sentence)
I have been to California (you had have experience being in California)

To make negative
has/ have + not + past participle

I haven't finished my homework.
she hasn't got her  book yet.