This is from a grammar book about aspect:
"What have you been doing today?" or "What have you done today?"
The best reply in both cases is in the same form as the question, but a present perfect simple reply to a present perfect continuous question shows that the job has been finished when it would not otherwise be clear. For example: "What have you been doing today?" "I have painted the bedroom windows." (clearly it is not in the same form)
My question is, if the best reply is in the same form, can I respond by saying"I have been painting the bedroom windows"? I have finished painting the windows, but I don't want to emphasize that, I just want to communicate my actions, even though they have been finished?