Mandarin has four tones. This is an unfamiliar concept to most native English speakers and is the type of thing one might ordinarily hope to learn in a class, with the assistance of a nice language teacher who would be able to address the inevitable perplexity that arises.

I don’t like to take classes. As an alternative, therefore, I viewed several YouTube videos on the subject of tones, to see whether I could benefit from YouTubers’ accumulated wisdom.

I was not generally enthralled.

This one was an exception. A cute young woman shows you, with the assistance of a notepad and a cat and a high energy level, how to handle what for many people is a challenging linguistic phenomenon.