皮 versus 支
the journal of Michael Werneburg
twenty-seven years and one million words
I have been using a kanji learning tool called "wanikani" for a year. I'm at the fifth level (of hell) and struggling with simultaneous pairings of kanji like 皮 and 支. One is "branch" and one is "skin". Another set is 自 versus 白, where the former is "oneself" and the latter is "white".
Another issue I've got is that it uses the same character in 'radical' form, 'kanji' form, and 'vocabulary' form at the same time, but the English meaning changes. For instance, the kanji 気 means "energy", while the vocabulary meaning is "spirit" and it will fail you for entering "energy".
And if you get it wrong even once, it can be weeks or months before you can try again. Which slows down my intake of new kanji. I'm now going along at 1/10th the speed I was when I started.