To use returned last week or Has returned last week.
The sentence is something like this:
Her father (returned/has returned) from Greece last week.
Now, I'm thinking both tense may work here.
Simple past tense:
He returned last week.
Well he returned and the act of 'returning' has happened 7 days earlier and we don't need to know anything after that. So, yes, He returned last week and maybe he will leave again today, or not.
Present perfect tense: We use this tense when the action took place in the past but the impact or effect of it is still visible in the present, right? So, he returned and is living here now—that is, he has not left again. So would "he has returned last week" work here?