hi.I'm a learner of English language.now I'm working on present perfect continues.how can I say I just finished reading a book 5 hours ago.is it true:"I've been finishing a book 5hours ago"? は 英語 (アメリカ) で何と言いますか？

質問を翻訳

Present continuous implies that the action is currently on-going. "Ago" implies that it is finished.

You would need to use past continuous:

"I was finishing a book 5 hours ago."

If you said that, I would assume that something interrupted you or happened either just before or just after you finished that you are now going to tell me about. I wouldn't use that sentence on its own just to tell someone I had finished a book.