With a camera or in a register? I must say that it is rather perverse that I now know how to say ward, papaya, and to register, but have no idea how to say hello, thank you, or please. I understand that there are limitations to the Duolingo format, but every other language on Duolingo I have looked at allows one to be polite in the language early.
I think the point early on with all of these random words was to emphasize the drastic difference in meaning/pronunciation between words that is caused by subtle things like accent changes or a changed letter. I haven't gotten far enough yet, but I presume the course teaches you the essentials of greetings/pleasantries soon enough, ideally.
I agree. It just seems to me a bit of a losing proposition to try to teach tones through recordings. Even if that works, though, I would have thought one could, for instance, have introduced the greetings or some typical adjectives along with whatever those syllables with another tone would be. We could, for instance, learn the greeting chao (sorry for the lack of tone markings) and whatever chao means with another tone.
You're right, it is hard to get a good grasp of the tones through the course audio alone, and it doesn't help that it's not guaranteed on every sentence. So it slightly defeats the purpose. I agree that something like what you said would be less inconvenient and confusing for learners in these "Alphabet" lessons. Hopefully in the making of a tree 2.0 in the future this will be considered.