You have definitely educated me on some interesting colloquial usage that I have never seen or heard, and for that I thank you. But I really think Duolingo has to draw the line at accepting colloquial answers--otherwise, how can they determine which colloquial usages to accept and which to disregard? Trying to make that decision would put them in the position of basically implying that one dialect is more valid than another, and I think we all agree that is not the case. So, rather than trying to navigate that minefield, it is better to stick to the answers that are correct in Standard English, even if it means a few answers that may be correct colloquially are not accepted.

In all honestly, I think we are completely on the same page about our core beliefs re: the validity of dialects (all are equally valid), and the important role of colloquial language in culture (it is a huge one). But if Duolingo tried to accept every colloquial or dialectical response in English, there could be hundreds of correct solutions for each exercise. And since those dialectical and colloquial responses are often only correct in very specific regions or circumstances, it would do more harm than good to do so. This specific question was regarding the proper way to express age in Standard English, and that is through the use of the verb "to be".

Thanks again for all the interesting information. I'd love to have some language chats some time--I'm a huge fan of linguistics studies, and any time I meet someone who is equally passionate about language issues, I get excited. :-)

thanks for the tip - am reporting it while checking other folks views.

Any tips on the difference between 'reporting' and commenting? I haven't seen how to report.