I am confused. The DL translation is first person plural imperative (Let's hope) - but there is no hint as to why it ought not to be indicative. There is no hint as to the object, except the feminine endings of the past participle statA and the ajective ultimA which should mean the object is a feminine noun or pronoun.
What am I missing?
it could be 'we hope it was the last one'.
'it' refers to 'ultima' and the verb is 'essere'. so the past participle must agree with 'ultima'. here is a page to address this. https://www.thoughtco.com/direct-object-pronouns-in-past-tense-2011704 at the bottom of the page.
'essere'. it's true that the past participle of stare is 'stato/a/i/e' but so is the past participle of 'essere'. in fact all of the compound tenses of the two verbs are identical. 'essere' is the verb used for identity. 'she is the director', 'it was the last'
here is a verb grammar that conjugates the two verbs and explains the uses with examples. 'essere' is verb 207 and 'stare' is verb 496. http://ge.tt/6fDnguA2/v/0?c
it's a little clunky to navigate but has tons of info.
'lo' is a direct object clitic and 'essere' is intransitive and doesn't take direct objects. here is a site that has information on pronouns. http://www.uvm.edu/~cmazzoni/3grammatica/grammatica/