Thank you for clarifying, this helps a lot to know.
As a long-term language learner, I'm used to checking up on other websites for explanations, pronunciations, and grammatical rules, but I sometimes worry that beginners to language learning might sometimes lack these sorts of clarifications and, by learning exclusively through Duolingo, may go a long time not quite understanding rules.
This point might be useful to add as one of the mandatory explanations which appear on screen the first time, as I've seen with other points. Maybe it could appear in the animals section?
Anyway, keep up the excellent work, this course is an absolute pleasure to work through x
The differences between masculine/feminine and singular/plural seem overwhelming at first, but just keep doing the exercises and reading through the sentences. It will all fall into place, and your mind will automatically start choosing the right one.. Memorizing the differences never worked for me, but repeated usage finally got my brain to comprehend it.