Yeah, I understand why it’s the way it is, but I still think it’s a poor system and could be done way better. The Japanese course has been public for several years now, so by now you would think they would have gone through and added some more acceptable phrases/alternatives. I know they had Japanese in beta for ages, so I feel that it should have way fewer issues than it does.
I tried Spanish just to see if that was any better, but being an absolute beginner, I quickly got frustrated by the lack of grammar explanations. I think that, as others have said, it’s probably only good for a few romance languages, and even then only for building vocabulary as an addition to another primary method of learning. In other words, it’s just not for me.