Items are arranged and items have been arranged
What is the difference between these sentences?
As far as I know, 'have been' is used when something that you are talking about has been done or ended.
'Items have been arranged' - To me, this means that the arrangement has been already done. The process is over.
'Item are arranged' - This sounds like the process is still not completely over.
Items are arranged
I interpret "arranged" in this sentence as an adjective describing "items". Specifically, "arranged" is a past participle. This sentence sounds like a simple statement about "items" that happen to be "arranged".
Items have been arranged
This statement clearly uses the passive voice where "have been arranged" is the verb phrase. This sentence strongly implies that "someone" did the arranging. The previous sentence did not have that implication.
Just to reiterate, the difference between these two sentences is the implication in the second that there is a "doer".